ThredUp (TDUP) 10-K 21 Mar 22 2021 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Mar. 15, 2022	Jun. 30, 2021
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-40249
Entity Registrant Name	ThredUp Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-4009181
Entity Address, Address Line One	969 Broadway
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Oakland
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94607
City Area Code	415
Local Phone Number	402-5202
Title of each class	Class A common stock, $0.0001 par value per share
Trading Symbol(s)	TDUP
Name of each exchange on which registered	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 1,340
Documents Incorporated by Reference	Portions of the registrant’s definitive Proxy Statement for the registrant’s 2022 Annual Meeting of Stockholders are incorporated by reference into Part III of this Annual Report on Form 10-K. Such Proxy Statement will be filed with the Securities and Exchange Commission within 120 days after the end of the registrant’s fiscal year ended December 31, 2021.
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Central Index Key	0001484778
Common stock Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		58,400,430
Common stock Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		40,383,662

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2021
Audit Information [Abstract]
Auditor Name	KPMG LLP
Auditor Location	San Francisco, California
Auditor Firm ID	185

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 84,550	$ 64,485
Marketable securities	121,277	0
Accounts receivable, net	4,136	1,823
Inventory, net	9,825	3,519
Other current assets	8,625	5,332
Total current assets	228,413	75,159
Operating lease right-of-use assets	39,340	23,656
Property and equipment, net	55,466	41,131
Goodwill	12,238	0
Intangible assets	13,854	0
Other assets	11,515	2,965
Total assets	360,826	142,911
Current liabilities
Accounts payable	13,336	9,386
Accrued and other current liabilities	45,253	32,541
Seller payable	19,125	13,724
Operating lease liabilities, current	3,931	3,643
Current portion of long-term debt	7,768	3,270
Total current liabilities	89,413	62,564
Operating lease liabilities, non-current	36,997	21,574
Long-term debt	27,559	31,190
Other non-current liabilities	1,123	2,719
Total liabilities	155,092	118,047
Commitments and contingencies (Note 12)
Convertible preferred stock: $0.0001 par value; 100,000 and 68,140 shares authorized as of December 31, 2021 and December 31, 2020, respectively; 0 and 65,971 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively, liquidation preference of $0 and $251,239 as of December 31, 2021 and 2020, respectively	0	247,041
Stockholders’ equity:
Class A and B common stock, $0.0001 par value; 1,120,000 and 110,000 shares authorized as of December 31, 2021 and December 31, 2020, respectively; 98,435 and 12,890 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively	10	1
Additional paid-in capital	522,161	29,989
Accumulated other comprehensive loss	(1,094)	0
Accumulated deficit	(315,343)	(252,167)
Total stockholders’ equity (deficit)	205,734	(222,177)
Total liabilities, convertible preferred stock and stockholders’ equity	$ 360,826	$ 142,911

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Liabilities, Convertible Preferred Stock and Stockholders’ Equity
Convertible preferred stock (in dollars per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized (in shares)	100,000,000	68,140,000
Convertible preferred stock, shares outstanding (in shares)	0	65,971,000
Convertible preferred stock, shares issued (in shares)	0	65,971,000
Liquidation preference	$ 0	$ 251,239
Stockholders’ equity:
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,120,000,000	110,000,000
Common stock, shares issued (in shares)	98,435,000	12,890,000
Common stock, shares outstanding (in shares)	98,435,000	12,890,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 251,792	$ 186,015	$ 163,812
Cost of revenue:
Total cost of revenue	73,660	57,867	51,308
Gross profit	178,132	128,148	112,504
Operating expenses:
Operations, product and technology	128,079	101,408	82,078
Marketing	63,625	44,765	44,980
Sales, general and administrative	48,814	28,564	22,253
Total operating expenses	240,518	174,737	149,311
Operating loss	(62,386)	(46,589)	(36,807)
Interest expense	(2,275)	(1,305)	(1,428)
Other income, net	1,565	73	74
Loss before provision for income taxes	(63,096)	(47,821)	(38,161)
Provision for income taxes	80	56	36
Net loss	$ (63,176)	$ (47,877)	$ (38,197)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.82)	$ (4.14)	$ (3.72)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.82)	$ (4.14)	$ (3.72)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	77,092,000	11,565,000	10,265,000
Weighted-average shares used in computing net loss per share attributable to common stockholders, diluted (in shares)	77,092,000	11,565,000	10,265,000
Consignment
Revenue:
Total revenue	$ 186,114	$ 138,096	$ 97,763
Cost of revenue:
Total cost of revenue	41,856	34,184	22,764
Product
Revenue:
Total revenue	65,678	47,919	66,049
Cost of revenue:
Total cost of revenue	$ 31,804	$ 23,683	$ 28,544

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (63,176)	$ (47,877)	$ (38,197)
Other comprehensive loss, net of tax:
Foreign currency translation adjustments	(729)	0	0
Unrealized gain (loss) on available-for-sale debt securities	(365)	0	2
Total comprehensive loss	$ (64,270)	$ (47,877)	$ (38,195)

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity - USD ($) $ in Thousands	Total	IPO	ASC842 Adoption (eff. January 1, 2020)	Common Stock	Common StockIPO	Additional Paid-in Capital	Additional Paid-in CapitalIPO	Accumulated Other Comprehensive Loss	Accumulated Deficit	Accumulated DeficitASC842 Adoption (eff. January 1, 2020)
Beginning balance (in shares) at Dec. 31, 2018	53,378,000
Beginning balance at Dec. 31, 2018	$ 164,394
Convertible Preferred Stock
Preferred stock issued/exercised (in shares)	12,550,000
Preferred stock issued/exercised	$ 82,511
Ending balance (in shares) at Dec. 31, 2019	65,928,000
Ending balance at Dec. 31, 2019	$ 246,905
Beginning balance (in shares) at Dec. 31, 2018				10,145,000
Beginning balance at Dec. 31, 2018	(153,446)			$ 1		$ 12,083		$ (2)	$ (165,528)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)				502,000
Exercise of stock options	722					722
Stock-based compensation	7,678					7,678
Net loss	2							2
Net loss	(38,197)								(38,197)
Ending balance (in shares) at Dec. 31, 2019				10,647,000
Ending balance at Dec. 31, 2019	$ (183,241)		$ (565)	$ 1		20,483		0	(203,725)	$ (565)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting standards update, extensible list	Accounting Standards Update 2016-02 [Member]
Preferred stock issued/exercised (in shares)	43,000
Preferred stock issued/exercised	$ 136
Ending balance (in shares) at Dec. 31, 2020	65,971,000
Ending balance at Dec. 31, 2020	$ 247,041
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)				2,243,000
Exercise of stock options	2,170					2,170
Stock-based compensation	7,336					7,336
Net loss	0
Net loss	$ (47,877)								(47,877)
Ending balance (in shares) at Dec. 31, 2020	12,890,000			12,890,000
Ending balance at Dec. 31, 2020	$ (222,177)			$ 1		29,989		0	(252,167)
Convertible Preferred Stock
Preferred stock conversion to Class B common stock (in shares)	(65,971,000)
Preferred stock conversion to Class B common stock	$ (247,041)
Ending balance (in shares) at Dec. 31, 2021	0
Ending balance at Dec. 31, 2021	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)				3,480,000
Exercise of stock options	5,267					5,267
Stock-based compensation	13,290					13,290
Conversion of preferred stock warrants to Class B common stock warrants	1,827					1,827
Preferred stock conversion to Class B common stock (in shares)				65,971,000
Preferred stock conversion to Class B common stock	247,041			$ 7		247,034
Class A common stock (in shares)				2,000,000	13,800,000
Class A common stock	45,525	$ 175,534		$ 1	$ 1	45,524	$ 175,533
Cashless exercise of common stock warrant (in shares)				128,643
Issuance of common stock to settle restricted stock units (in shares)				84,000
Withholding taxes for the net share settlement of restricted stock units (in shares)				(1,000)
Withholding taxes for the net share settlement of restricted stock units	(29)					(29)
ESPP purchase (in shares)				82,000
ESPP purchase	982					982
Acquisition delayed share issuance	2,744					2,744
Other comprehensive loss	(1,094)							(1,094)
Net loss	(365)
Net loss	$ (63,176)								(63,176)
Ending balance (in shares) at Dec. 31, 2021	98,435,000			98,435,000
Ending balance at Dec. 31, 2021	$ 205,734			$ 10		$ 522,161		$ (1,094)	$ (315,343)

Consolidated Statements of Co_2

Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Statement of Stockholders' Equity [Abstract]
Issuance costs	$ 3,881

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (63,176)	$ (47,877)	$ (38,197)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	9,155	5,581	4,274
Stock-based compensation expense	12,959	7,336	7,678
Reduction in the carrying amount of right-of-use assets	3,985	4,034
Changes in fair value of convertible preferred stock warrants and others	2,342	561	1,077
Changes in operating assets and liabilities:
Accounts receivable, net	(1,189)	229	(638)
Inventory, net	(2,741)	374	2,290
Other current and non-current assets	(6,326)	32	(239)
Accounts payable	871	3,469	(741)
Accrued and other current liabilities	9,251	5,182	14,205
Seller payable	5,072	4,407	315
Operating lease liabilities	(3,964)	(3,824)
Other non-current liabilities	(1,258)	1,391	(114)
Net cash used in operating activities	(35,019)	(19,105)	(10,090)
Cash flows from investing activities
Purchases of marketable securities	(125,217)	0	0
Maturities of marketable securities	2,800	0	8,250
Purchases of non-marketable equity investment	(3,750)	0	0
Acquisition of business, net of cash acquired	(23,581)	0	0
Purchase of property and equipment	(19,828)	(19,424)	(9,504)
Net cash used in investing activities	(169,576)	(19,424)	(1,254)
Cash flows from financing activities
Proceeds from debt issuance	4,625	18,352	19,750
Repayment of debt	(4,000)	(1,190)	(11,801)
Proceeds from offerings of issuance of Class A common stock, net of underwriting discounts and commissions	226,905	0	0
Proceeds from exercise of common stock options and withholding taxes for the net share settlement of restricted stock units	5,177	2,170	722
Payment of costs for the initial public offering and the follow-on offering	(4,729)	(1,117)	0
Proceeds from issuance of convertible preferred stock, net of issuance costs	0	0	82,511
Proceeds from ESPP purchase	982	0	0
Net cash provided by financing activities	228,960	18,215	91,182
Effect of exchange rate changes on cash and cash equivalents	(64)	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	24,301	(20,314)	79,838
Cash, cash equivalents and restricted cash
Beginning of period	67,539	87,853	8,015
End of period	91,840	67,539	87,853
Supplemental disclosures of cash flow information
Cash paid for income taxes, net of refunds	64	45	27
Cash paid for interest	2,076	1,450	1,207
Supplemental disclosures of non-cash investing and financing activities
Purchases of property and equipment included in accounts payable and accrued liabilities	3,739	1,555	$ 587
Right-of-use assets obtained in exchange for operating lease liabilities with lease modification	$ 19,669	$ 9,142

Organization and Description of

Organization and Description of Business	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business ThredUp Inc. (“ThredUp” or the “Company”) was formed as a corporation in the State of Delaware in January 2009. ThredUp is a large resale platform that enables consumers to buy and sell primarily secondhand women’s and kid’s apparel, shoes and accessories. The Company conducts its marketing and administrative functions from Oakland, California and Scottsdale, Arizona and operates its fulfillment centers in Pennsylvania, Georgia and Arizona. Another distribution center in Texas is under construction. The Company expanded its operations to Europe through its acquisition of Remix, which closed in October 2021. Initial Public Offering The Company’s registration statement on Form S-1 related to its initial public offering (the “IPO”) was declared effective on March 25, 2021 by the Securities and Exchange Commission (“SEC”), and the Company’s Class A common stock began trading on the Nasdaq Global Select Market on March 26, 2021. Upon the closing of the IPO, the Company sold 13,800,000 shares of Class A common stock to the public at a price of $14.00 per share. The aggregate net proceeds were $175.5 million after deducting offering costs, underwriting discounts and commissions of $17.7 million. Immediately prior to the completion of the IPO, the Company filed its Amended and Restated Certificate of Incorporation, which authorized a total of 1,000,000,000 shares of Class A common stock, 120,000,000 shares of Class B common stock and 100,000,000 shares of undesignated preferred stock. Immediately prior to the completion of the IPO, 65,970,938 shares of the convertible preferr ed stock then outstanding were converted into an equivalent number of shares of Class B common stock. The Company reclassified the convertible preferred stock to Class B common stock and additional paid-in capital upon the conversion in the three months ended March 31, 2021. 12,889,760 shares of the outstanding historical common stock were reclassified into an equivalent number of shares of Class B common stock. 164,973 shares of the convertible preferred stock warrants were converted to an equivalent number of shares of Class B common stock warrants. Follow-on Public Offering On August 2, 2021, the Company issued and sold 2,000,000 shares of Class A common stock at a price of $24.25 per share in a registered public offering. The aggregate net proceeds were $45.5 million, after deducting $3.3 million of underwriting discounts and commissions and offering costs. Refer to Note 10, Common Stock and Common Stock Warrants for more details.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Presentation and Use of Estimates The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany account balances and transactions have been eliminated upon consolidation. The preparation of consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the amounts that are reported in the consolidated financial statements and the related disclosures. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include, but are not limited to, the useful lives of property and equipment and intangibles, allowance for sales returns, allowance for bad debts, breakage on loyalty points and rewards, valuation of inventory, warrants, stock-based compensation, valuation of right-of-use assets, valuation of goodwill and acquired intangibles and income taxes. The COVID-19 pandemic has adversely impacted businesses worldwide and has impacted various aspects of the Company’s business and operations. The Company’s revenue growth and operating spend has been and may continue to be affected by COVID-19 and related restrictions on business, labor cost increases and supply chain issues. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of significant judgment. Foreign Currency The Company’s functional currency is the United States (“U.S.”) dollar for its operations except for Remix whose functional currency is the Bulgarian lev. In accordance with authoritative guidance, assets and liabilities of the Company’s foreign operations are translated from the respective functional currencies into U.S. dollars at period-end rates, while income and expenses are translated using the average exchange rate during the period in which the transactions occurred. The related translation adjustments are reflected as a foreign currency translation adjustment in accumulated other comprehensive income (loss). Revenue Recognition Revenue is recognized in accordance with Accounting Standards Topic 606 (“ASC 606”). Under ASC 606, revenue is recognized upon transfer of control of promised goods and services to customers in an amount that reflects the consideration the Company expects to receive for those goods and services. The Company generates the majority of its revenue from its marketplace, which allows its buyers to browse and purchase resale items for women’s and kids’ apparel, shoes and accessories on behalf of sellers. The Company recognizes revenue through the following steps: (1) identification of the contract, or contracts, with the customer; (2) identification of the performance obligations in the contract; (3) determination of the transaction price; (4) allocation of the transaction price to the performance obligations in the contract; and (5) recognition of revenue when, or as, it satisfies a performance obligation. Both buyers and sellers may be customers in the Company’s revenue arrangements. Sellers are the primary customer in a consignment arrangement while the buyer is the primary customer in sale of Company-owned inventory, referred to as product sales. A contract with a customer exists in both cases when the end-customer purchases the goods obligating the Company to deliver the identified performance obligation(s). Generally, the Company requires authorization from a credit card or other payment method (such as PayPal), or verification of receipt of payment, before the products are shipped to buyers. The Company generally receives payments from buyers before payments to the sellers are due. Consignment Revenue The Company generates consignment revenue from the sale of secondhand women’s and kids’ apparel, shoes and accessories on behalf of sellers. The Company retains a percentage of the proceeds received as payment for its consignment service. The Company reports consignment revenue on a net basis as an agent and not the gross amount collected from the buyer. Title to the consigned goods remain with the consignor until transferred to the buyer, which occurs subsequent to purchase of the consigned goods and upon expiration of the allotted return period. The Company does not take title of consigned goods at any time except in certain cases where the consignment window expires or returned goods become Company-owned inventory. Consignment revenue is recognized upon purchase of the consigned good by the buyer as its performance obligation of providing consignment services to the consignor is satisfied at that point. Consignment revenue is recognized net of seller payouts, discounts, incentives and returns. Sales tax assessed by governmental authorities is excluded from revenue. Product Revenue The Company recognizes product revenue on a gross basis as the Company acts as the principal in the transaction. Online sales and sales to third-party retail partners are generally recognized upon shipment of the purchased good to the buyer. Product revenue is recognized net of discounts, incentives and returns. Sales tax assessed by governmental authorities is excluded from revenue. Shipping Fees The Company charges shipping fees to buyers, which are included in revenue. All outbound shipping costs are accounted for in cost of revenue at the time revenue is recognized. Returns The Company generally has a 14-day return period which may change from time to time and recognizes a returns reserve, based on historical experience, which is recorded in accrued and other current liabilities on the consolidated balance sheet. Incentives Incentives include website discounts, customer credits and loyalty program rewards issued to sellers and buyers. Incentives are treated as a reduction of product revenue and consignment revenue. Revenue treatment for our loyalty program is discussed further below under Deferred Revenue. Deferred Revenue Deferred revenue consists primarily of cash collections for product items purchased, but not shipped, and revenue allocated to unredeemed loyalty points. Cash collections for items purchased, but not shipped, are generally recognized as revenue upon shipment. As of December 31, 2021 and 2020, the Company had $1.7 million and $0.9 million, respectively, in deferred revenue for such items, which were recognized shortly after the period end, and are included in accrued and other current liabilities on the consolidated balance sheets. In August 2019, the Company launched a customer loyalty program that provides customers with rewards that can be applied to future purchases or other incentives. Loyalty points and rewards are accounted for as separate performance obligations and accrued as deferred revenue in the amount of the transaction price allocated to the points and rewards. The allocated transaction price is based on the estimated fair value per point, net of breakage. Breakage is estimated based on the Company’s historical redemption rates. Revenue is recognized when the loyalty rewards are redeemed or expire. As of December 31, 2021 and 2020, the Company had a liability of $4.0 million and $4.1 million, respectively, related to the loyalty program which is included in accrued and other current liabilities in the consolidated balance sheets. The Company recognized $13.8 million, $6.6 million and $0.1 million of revenue related to loyalty points in the 2021, 2020 and 2019 periods, respectively. Revenue allocated to loyalty points is expected to be recognized within one year as loyalty points expire 12 months after issuance. Revenue by Geographic Area Revenue is attributed to a geographic area based on the shipped-from location. The following summarizes the Company’s revenue by geographic area (in thousands): Year Ended December 31, 2021 December 31, 2020 December 31, 2019 North America $ 240,677 $ 186,015 $ 163,812 Europe 11,115 — — Total $ 251,792 $ 186,015 $ 163,812 Europe net sales in the year ended December 31, 2021 is primarily coming from the Company’s Remix operations acquired in 2021. Segments The Company operates under one operating segment and one reportable segment as its chief operating decision maker, who is its Chief Executive Officer, reviews financial information presented on a consolidated basis for purposes of making operating decisions, allocating resources and evaluating financial performance. The long-lived assets, excluding goodwill and intangible assets, outside of the United States are immaterial. Business Combinations The Company accounts for business combinations using the acquisition method of accounting, which requires, among other things, allocation of the fair value of purchase consideration to the tangible and intangible assets acquired and liabilities assumed at estimated fair values on the acquisition date. The excess of the fair value of purchase consideration over the values of these identifiable assets and liabilities is recorded as goodwill. When determining the fair value of assets acquired and liabilities assumed, the management makes significant estimates and assumptions, especially with respect to intangible assets. Significant estimates in valuing intangible assets include, but are not limited to, expected future cash flows, which includes consideration of future growth and margins, future changes in technology, brand awareness and discount rates. Fair value estimates are based on the assumptions that management believes to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. After the purchase accounting is finalized, any subsequent adjustments are reflected in the consolidated statements of operations. Acquisition costs, such as legal and consulting fees, are expensed as incurred. Net Loss Per Share Attributable to Common Stockholders The Company follows the two-class method when computing net loss per common share when shares issued meet the definition of participating securities. The two-class method determines net loss per share for each class of common stock and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income available to stockholders for the period to be allocated between common stock and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed. The Company’s convertible preferred stock contractually entitles the holders of such shares to participate in dividends but does not contractually require the holders of such shares to participate in the Company’s losses. The rights, including the liquidation and dividend rights and sharing of losses, of the Class A common stock and Class B common stock are identical, other than voting rights. As the liquidation and dividend rights and sharing of losses are identical, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share attributed to common stockholders will, therefore, be the same for both Class A and Class B common stock on an individual or combined basis. For periods in which the Company reports net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Comprehensive Loss Comprehensive loss is comprised of net loss and other charges or credits to equity that are not the result of transactions with owners. There was $0.7 million foreign currency translation loss included in the other comprehensive loss for the year ended December 31, 2021. There were $0.4 million other comprehensive losses related to unrealized gains or losses on debt securities classified as available-for-sale for the year ended December 31, 2021. There were no material unrealized gains or losses for the years ended December 31, 2020 and 2019. Cash, Cash Equivalents and Restricted Cash The Company classifies all highly liquid instruments with an original maturity of three months or less at the time of purchase as cash equivalents. Cash and cash equivalents are comprised of bank deposits and commercial paper, and money market funds. Restricted cash primarily represents letters of credit with financial institutions held as collateral for its facility leases. Restricted cash is classified non-current if the Company expects that the cash will remain restricted for a period greater than one-year. Current restricted cash is included in other current assets on the consolidated balance sheet. The following table provides a reconciliation of cash and cash equivalents as well as restricted cash reported within the consolidated balance sheets to the amounts shown in the consolidated statements of cash flows (in thousands): December 31, 2021 2020 Cash and cash equivalents $ 84,550 $ 64,485 Restricted cash, current 560 364 Restricted cash, non-current 6,730 2,690 Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows $ 91,840 $ 67,539 Restricted cash, non-current of $6.7 million and $2.7 million is included in other assets in the consolidated balance sheets as of December 31, 2021 and 2020, respectively. Marketable Securities The Company invests its excess cash in investment grade, short to intermediate-term, fixed income securities and recognizes the transaction on the trade-date. The Company’s marketable securities are classified as available-for-sale in current assets because they represent investments of cash available for current operations. Marketable securities are reported at fair value with unrealized gains and losses reported, net of tax, as a separate component of accumulated other comprehensive gain (loss) until realized. The marketable securities are reviewed periodically to identify possible other-than-temporary impairments. Realized gains or losses and other-than-temporary impairments, if any, on available-for sale securities are reported in other income, net as incurred. Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents, marketable securities and accounts receivable. The Company deposits cash at major financial institutions, and at times, such cash may exceed federally insured limits. The credit risk is believed to be minimal due to the financial position of the depository institutions in which those deposits are held. The Company has never experienced any losses on deposits since inception. The Company’s investment policy restricts cash investments to highly liquid, short to intermediate-term, high grade fixed income securities, and as a result, the Company believes its cash equivalents and marketable securities represent minimal credit risk. As of December 31, 2021 and 2020, there were no customers that represented 10% or more of the Company’s accounts receivable balance. There were no customers that individually exceeded 10% of the Company’s revenue for the years ended December 31, 2021, 2020 and 2019. Accounts Receivable, Net Accounts receivable consists of amounts due from payment processors and trade customers that do not bear interest. The Company records an allowance for doubtful accounts for estimated losses inherent in its trade accounts receivable portfolio. In establishing the required allowance, management considers historical losses adjusted for current market conditions, the financial condition of the customer, the amount of receivables in dispute, and the current receivables aging and payment patterns. The Company does not have any off-balance sheet credit exposure related to its customers. The allowance for doubtful accounts was immaterial as of December 31, 2021 and 2020. Inventory, Net Inventories, consisting of merchandise that the Company has purchased and holds title, are accounted for using the specific identification method, and are valued at the lower of cost and net realizable value. The cost of inventory is equal to the cost of the merchandise paid to the seller and related inbound shipping costs. Inventory valuation requires the Company to make judgments based on currently available information about the likely method of disposition, such as through sales to individual customers or liquidations, and expected recoverable values of each disposition category. The Company records an inventory write-down based on the age of the inventory and historical experience of expected sell-through. Property and Equipment, Net Property and equipment are stated at cost less accumulated depreciation. Depreciation is recorded on a straight-line basis over the estimated useful lives of the assets. The estimated useful lives of the Company’s property and equipment are as follows: Machinery and equipment 3-10 years Internal-use software 1-3 years Leasehold improvements Shorter of lease term or estimated useful life Computers and software 2-3 years Furniture and fixtures 5-7 years Maintenance and repairs are charged to expense as incurred, and improvements and betterments are capitalized. When assets are retired or otherwise disposed of, the cost and accumulated depreciation and amortization are removed from the balance sheet and any resulting gain or loss is reflected in the consolidated statement of operations in the period realized. Internal-Use Software The Company capitalizes qualifying proprietary software development costs that are incurred during the application development stage. Capitalization of costs begins when two criteria are met: (i) the preliminary project stage is completed, and (ii) it is probable that the software will be completed and placed in service for its intended use. Capitalization ceases when the software is substantially complete and ready for its intended use including the completion of all significant testing. Costs related to preliminary project activities and post implementation operating activities are expensed as incurred. Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset group may not be recoverable. Recoverability of assets held and used is measured by comparison of the carrying amount of an asset to the future undiscounted cash flows expected to be generated from the use of the asset and its eventual disposition. If such assets are considered to be impaired, the impairment to be recognized is equal to the excess of the fair value over the carrying amount of the impaired assets. There were no impairments of long-lived assets for the years ended December 31, 2021 and 2020. Goodwill Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in a business combination. Goodwill is not subject to amortization, but is reviewed for impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying value of goodwill may not be recoverable. The Company tests goodwill for impairment annually as of the first day of its fourth fiscal quarter and in interim periods if events occur that would indicate that the carrying value of goodwill may be impaired. The Company assesses goodwill for impairment by comparing the fair value of the reporting unit to its carrying amount. Acquired Intangible Assets When a business is acquired, a portion of the purchase price is typically allocated to identifiable intangible assets, such as trademark, acquired technology and customer relationships. Fair value of these assets is determined primarily using the income approach, which requires the management to project future cash flows and apply an appropriate discount rate. Intangible assets with finite lives are amortized on a straight-line basis over their economic lives ranging from 3 years to 9 years. Estimates are based upon assumptions believed to be reasonable but which are inherently uncertain and unpredictable. Assumptions may be incomplete or inaccurate, and unanticipated events and circumstances may occur. Incorrect estimates could result in future impairment charges, and those charges could be material to the Company’s results of operations. Other Investment The Company made a strategic investment in preferred shares of a privately held online retail company in October 2021. The Company accounts for its investment in accordance with ASC 321 , Investments – Equity Securities (“ASC 321”). Upon acquisition, the investment is measured at cost, which represents the then fair value. Under ASC 321, the Company can elect to subsequently measure the investments at initial cost, minus impairment and any changes, plus or minus, resulting from observable price in orderly transactions for the identical or a similar investment of the same issuer. This election must be made for each investment separately. Changes in the carrying value of other investment are recognized through net loss. Each reporting period, the Company performs a qualitative assessment to evaluate whether the investment is impaired. The Company’s assessment includes a review of recent operating results and trends, recent sales/acquisitions of the investee securities and other factors that raise concerns about the investee’s ability to continue as a going concern. If the investment is impaired, an impairment charge is recognized in the amount by which the carrying amount of the investment exceeds the estimated fair value of the investment, with the impairment charge recognized through net loss. The Company’s non-marketable equity investment of $3.8 million was included in the other assets in the consolidated balance sheet as of December 31, 2021 and there was no impairment recognized on the investment. Asset Retirement Obligations The Company records asset retirement obligations (“AROs”) for the estimated cost of restoring its automated warehouse facilities to the specific condition required per the terms of its lease agreement, upon termination of the lease. AROs represent the present value of the expected costs and timing of the related obligations incurred. The ARO assets and liabilities are recorded in property and equipment within the machinery and equipment line item and other non-current liabilities in the consolidated balance sheets. The Company records accretion expense, which represents the increase in the ARO, over the remaining estimated duration of the lease including renewal periods that are included in the lease life. Accretion expense is recorded in operations, product and technology expense in the consolidated statement of operations using accretion rates based on credit adjusted risk-free interest rates. Leases Effective January 1, 2020, the Company adopted ASC 842, Leases (“ASC 842”), using the optional transition method and applied the standard only to leases that existed at that date. Under ASC 842, the Company determines if an arrangement is or contains a lease at inception by assessing whether the arrangement contains an identified asset and whether it has the right to control the identified asset. Lessees are required to classify leases as either finance or operating leases and to record a right-of-use (“ROU”) asset and a lease liability for all leases with a term greater than 12 months regardless of the lease classification. The lease classification will determine whether the lease expense is recognized based on an effective interest rate method or on a straight-line basis over the term of the lease. The Company determines the initial classification and measurement of its ROU assets and lease liabilities at the lease commencement date and thereafter if modified. ROU assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Lease liabilities are recognized at the lease commencement date based on the present value of future lease payments over the lease term. ROU assets are based on the measurement of the lease liability and also include any lease payments made prior to or on lease commencement and exclude lease incentives and initial direct costs incurred, as applicable. As the implicit rate in the Company's leases is generally unknown, the Company uses its incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future lease payments. The Company gives consideration to its existing credit arrangements, term of the lease, total lease payments and adjust for the impacts of collateral, as necessary, when calculating its incremental borrowing rates. The lease terms may include options to extend or terminate the lease when it is reasonably certain the Company will exercise any such options. Lease costs for the Company's operating leases are recognized on a straight-line basis within operating expenses over the lease term. The Company has elected to not separate lease and non-lease components for real estate leases and, as a result, accounts for lease and non-lease components as one component. The Company has also elected to not apply the recognition requirement to any leases within its existing classes of assets with a term of 12 months or less. For these leases, lease payments are recognized on a straight-line basis over the lease term and variable payments in the period in which the obligation is incurred. Seller Payable Seller payable includes amounts owed to sellers upon the purchase of sellers’ goods by the Company or by buyers. Amounts are initially provided as a credit to sellers. These credits may be applied towards purchases from the Company, converted to third-party retailer or thredUP gift cards or redeemed for cash. Gift Cards and Site and Seller Credits The Company sells thredUP gift cards on its e-commerce website. Seller credits and site credits can be converted to thredUP gift cards. thredUP gift cards do not expire or lose value over periods of inactivity. The Company accounts for gift cards by recognizing a gift card liability at the time a gift card is delivered to the customer. As of December 31, 2021 and 2020, $7.3 million and $6.2 million of gift card liability, respectively, was included in accrued and other current liabilities on the consolidated balance sheets. Revenue from gift cards is generally recognized when the gift cards are redeemed by the customer and amounted to $0.9 million, $0.6 million and $0.1 million in the years ended December 31, 2021, 2020, and 2019 respectively. The Company issues both site credits and seller credits. The Company issues site credits for various reasons such as for promotions or for refunds. The Company issues seller credits to sellers in exchange for consignment items sold. Site credits can be applied towards future charges but cannot be converted into cash. Site credits and seller credits may also be converted to thredUP gift cards after one year at the discretion of the Company. These credits are recognized as revenue when used, converted, or expired. As of December 31, 2021 and 2020, $5.9 million and $3.2 million, respectively, of such customer site credits were included in accrued and other current liabilities on the consolidated balance sheets. Breakage on gift cards and site credits is immaterial for the years ended December 31, 2021, 2020 and 2019. Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income on the years in which those temporary differences are expected to be recovered and settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company records interest and penalties related to unrecognized tax benefits in income tax expense. Cost of Revenue Cost of consignment revenue consists of outbound shipping, outbound labor and packaging costs. Cost of product revenue mainly consists of the inventory cost, inbound shipping related to the sold merchandise, outbound shipping, outbound labor, packaging costs and inventory write-downs. Operations, Product and Technology Operations, product and technology expenses consist primarily of distribution center operating costs and product and technology expenses. Distribution center operating costs include personnel costs, distribution center rent, maintenance and equipment depreciation as well as inbound shipping costs, other than those capitalized in inventory. Product and technology costs include personnel costs for the design and development of product and the related technology that is used to operate the distribution centers, merchandise science, website development and related expenses for these departments. Operations, product and technology expenses also include an allocation of corporate facilities and information technology costs including equipment, depreciation and rent. Research and development costs related to our technology were approximately $28.7 million, $20.7 million and $19.0 million, during the years ended December 31, 2021, 2020 and 2019, respectively. Marketing Marketing costs consist primarily of advertising, public relations expenditures and personnel costs for employees engaged in marketing. Marketing costs also include an allocation of corporate facilities and information technology costs including equipment, depreciation and rent. Advertising and other promotional costs included in the marketing line item on the consolidated statement of operations are expensed as incurred and were approximately $54.1 million, $38.4 million and $39.2 million for the years ended December 31, 2021, 2020 and 2019, respectively. Sales, General and Administrative Sales, general and administrative expenses consist of personnel costs for employees involved in general corporate functions, including accounting, finance, tax, legal and people services; customer service; and retail stores. Sales, general and administrative also includes payment processing fees, professional fees and allocation of corporate facilities and information technology costs such as equipment, depreciation and rent. Stock-Based Compensation Stock-based compensation costs are based on the fair values on the date of grant for stock awards and stock options and on the date of enrollment for the employee stock purchase plan (“ESPP”). The fair values of Restricted Stock Units (“RSUs”) are based on ThredUp’s stock price on the date of grant. The fair values of stock options and ESPP are estimated using the Black-Scholes option-pricing model. The fair values of equity awards are recognized as compensation expense over the requisite service period or over the period in which the related services are received (generally the vesting period), using the straight-line method. The estimated fair value of equity awards that contain performance conditions is expensed over the term of the award once the Company has determined that it is probable that performance conditions will be satisfied. The Company accounts for forfeitures as they occur. The determination of fair value for share-based awards on the date of grant using an option pricing model requires management to make certain assumptions regarding subjective variables. Prior Period Reclassifications Within the consolidated balance sheets, the Company included restricted cash, non-current within non-current other assets for the prior period to conform with current period presentation. Fair Value Measurements Fair value accounting is applied for all financial assets and liabilities that are recognized or disclosed at fair valu

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Value Measurements	Financial Instruments and Fair Value Measurements For all of the marketable securities, the Company utilizes third-party pricing services to obtain fair value. Third-party pricing methodologies incorporate bond terms and conditions, current performance data, proprietary pricing models, real-time quotes from contributing dealers, trade prices and other market data. The following table provides the financial instruments measured at fair value for each of the respective periods (in thousands): Fair Value as of December 31, 2021 Level 1 Level 2 Level 3 Total Assets Money market fund $ 41,376 $ — $ — $ 41,376 U.S. treasury securities 37,190 — — 37,190 Commercial paper — 12,098 — 12,098 Corporate debt securities 55,921 — — 55,921 U.S. government agency bonds 28,166 — — 28,166 Total $ 162,653 $ 12,098 $ — $ 174,751 Classified as: Cash equivalents $ 53,474 Marketable securities 121,277 $ 174,751 December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 43,460 $ — $ — $ 43,460 Total cash equivalents $ 43,460 $ — $ — $ 43,460 Liabilities Convertible preferred stock warrant liability $ — $ — $ 805 $ 805 Total liabilities $ — $ — $ 805 $ 805 The Company’s money market funds and commercial paper were included within cash equivalents. U.S. treasury securities, U.S. government agency bonds and corporate debt securities were included within the marketable securities. The Company’s money market funds, U.S. treasury securities, corporate debt securities, U.S. government agency bonds were valued using Level 1 inputs because they are valued using quoted market prices. The Company’s commercial papers were valued using Level 2 inputs because they are valued using quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. As of December 31, 2021 and 2020 the amortized cost of the Company’s financial assets and liabilities approximate their estimated fair values. As of December 31, 2021, out of the $121.3 million carrying amount of marketable securities, $49.0 million had a contractual maturity date of less than one year and $72.2 million had a contractual maturity date between one and two years. The convertible preferred stock warrant liability was included in other non-current liabilities and was valued using Level 3 inputs, before the convertible preferred stock warrants were converted to Class B common stock warrants upon IPO.

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net consists of the following (in thousands): December 31, 2021 2020 Machinery and equipment $ 48,874 $ 35,254 Internal-use software 5,517 4,764 Computers and software 5,336 3,677 Leasehold improvements 4,705 4,459 Furniture and fixtures 856 519 Construction in progress 10,740 6,548 76,028 55,221 Less: accumulated depreciation and amortization (20,562) (14,090) Property and equipment, net $ 55,466 $ 41,131

Acquisition of Remix

Acquisition of Remix	12 Months Ended
	Dec. 31, 2021
Business Combination and Asset Acquisition [Abstract]
Acquisition of Remix	Acquisition of Remix On July 24, 2021, the Company entered into Share Purchase Agreements with the shareholders of Remix, a fashion resale company headquartered in Sofia, Bulgaria, to purchase 100% of the outstanding equity interests of Remix and its subsidiary. The acquisition of Remix closed on October 7, 2021. With this acquisition, the Company added a complementary operational infrastructure and an experienced management team to enable its expansion into Europe. The Company acquired the business for total cash consideration of $25.6 million and future issuance of 130,597 Class A common shares in 2023 with a fair value of $2.7 million as of the closing date. Revenue of $11.1 million and net loss of $1.2 million from this acquisition have been included in the consolidated statements of operations from the acquisition date through December 31, 2021. The Company incurred $1.1 million in transaction-related costs during the year ended December 31, 2021, which are included within sales, general and administrative expenses. The allocation of the purchase price is based on the estimated fair values of the assets acquired and liabilities assumed by major class related to the acquisition of Remix and are reflected, as of the acquisition date, in the accompanying financial statements as follows (in thousands): Purchase Price Cash consideration $ 25,550 Delayed share issuance 2,744 Total purchase consideration $ 28,294 Cash and cash equivalents 1,860 Accounts receivable 1,150 Inventory 3,657 Intangible assets 14,800 Other assets 786 Accounts payable (3,102) Accrued and other liabilities (3,356) Total net assets acquired 15,795 Goodwill as of October 7, 2021 $ 12,499 Foreign currency translation adjustments (261) Goodwill as of December 31, 2021 $ 12,238 Goodwill was calculated as the excess of the consideration transferred over the net assets acquired and represents the estimated future economic benefits arising from other assets acquired, the assembled workforce and planned growth in strategic markets that could not be individually identified and separately recognized. Goodwill recognized as a result of this acquisition is not deductible for tax purposes. Intangible assets with determinable lives Customer relationships $ 5,200 Developed technology 4,900 Trademarks 4,700 Total identified intangible assets as of October 7, 2021 $ 14,800 Foreign currency translation adjustments (308) Gross carrying amount as of December 31, 2021 $ 14,492 Customer relationships represent the fair value of future projected revenue that will be derived from sales of products to existing customers of Remix business. Customer relationships were valued using the multi-period excess earning method of the income approach. Developed technology primarily consists of a client facing platform (i.e., website and mobile app) and supporting functions, all of which were internally developed. Trademarks relates to the “Remix” trade name. Developed technology and trademarks were valued using the relief-from-royalty method under the income approach. This method involves forecasting avoided royalties, reducing them by taxes and discounting the resulting net cash flows to a present value using an appropriate discount rate that requires judgement by management. The Company did not present pro forma and other financial information for the acquisition of Remix, as this is not considered to be a material business combination.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible AssetsThe goodwill is primarily attributable to the planned growth in the combined business after the acquisition of Remix. Goodwill is not amortized to earnings, but instead is reviewed for impairment at least annually, absent any interim indicators of impairment. The carrying amount of goodwill was $12.2 million as of December 31, 2021. The gross carrying amounts and accumulated amortization of the intangible assets with determinable lives are as follows (in thousands): As of December 31, 2021 Intangible assets with determinable lives Amortization Period (years) Gross carrying amount Accumulated Carrying amount, net Customer relationships 8 $ 5,092 $ (150) $ 4,942 Developed technology 3 4,798 (373) 4,425 Trademarks 9 4,602 (115) 4,487 Total $ 14,492 $ (638) $ 13,854 Developed technology, customer relationships, and trademarks intangibles amortization is recorded within operations, product and technology, sales general and administrative, and marketing expense lines, respectively, within the Consolidated Statements of Operations.

Balance Sheet Components

Balance Sheet Components	12 Months Ended
	Dec. 31, 2021
Balance Sheet Components [Abstract]
Balance Sheet Components	Balance Sheet Components Inventories consist of the following (in thousands): December 31, 2021 2020 Raw materials $ 908 $ — Work in progress 670 — Finished goods 8,247 3,519 $ 9,825 $ 3,519 Accrued and other current liabilities consist of the following (in thousands): December 31, 2021 2020 Gift card and site credit liabilities $ 13,223 $ 9,362 Accrued compensation 6,438 3,443 Accrued vendor liabilities 6,031 3,407 Deferred revenue 5,878 5,094 Accrued taxes 5,728 4,594 Allowance for returns 6,209 3,389 Accrued other 1,746 3,252 $ 45,253 $ 32,541

Lease Agreements

Lease Agreements	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Lease Agreements	Lease Agreements The Company leases certain office space and distribution centers with lease terms ranging from 20 to 146 months. These leases require monthly lease payments that may be subject to annual increases throughout the lease term. Certain of these leases also include renewal options at the election of the Company to renew or extend the lease for an additional 12 to 120 months. For certain leases, these optional periods have been considered in the determination of the right-of-use assets and lease liabilities associated with these leases as the Company has determined it is reasonably certain it will exercise the renewal options. The majority of the Company’s existing office space and distribution center in Europe are short-term leases as of December 31, 2021. In December 2021, the Company entered into an agreement to lease a new headquarter office and distribution center in Sophia, Bulgaria (the “Bulgaria Lease”). The Bulgaria Lease is expected to commence in March 2022 with an original term of 10 years from the commencement date. The base rent is approximately €14.1 million or $15.9 million, estimated at December 31, 2021 Euro to USD spot rate, in aggregate over the original term. The following table summarizes maturities of the Company’s operating lease liabilities as of December 31, 2021 (in thousands): December 31, 2022 $ 7,931 2023 7,808 2024 6,930 2025 6,061 2026 5,706 Thereafter 26,437 Total lease payments 60,873 Less: imputed interest (13,843) Less: tenant improvement allowance yet to be received (6,102) Total lease liabilities 40,928 Less: current lease liabilities (3,931) Total non-current lease liabilities $ 36,997 Security deposits and letters of credits used to secure the leases were $0.8 million and $6.3 million, respectively, as of December 31, 2021 and $0.3 million and $3.1 million, respectively, as of December 31, 2020. Operating lease cost was $7.0 million and $6.8 million for the years ended December 31, 2021 and 2020, respectively. Rent expense for operating leases under ASC 840 was $4.4 million for the year ended December 31, 2019. The following table summarizes the cost components of the Company’s operating leases (in thousands): Year Ended December 31, 2021 2020 Operating Lease Cost Fixed Cost $ 5,591 $ 5,568 Short-Term Lease Cost 7 58 Variable Lease Cost (1) 1,381 1,197 Total Operating Lease Cost (2) $ 6,979 $ 6,823 ________________ (1) Under the terms of the lease agreements, the Company is also responsible for certain variable lease payments that are not included in the measurement of the lease liability. Variable lease payments include non-lease components such as common area maintenance fees. (2) The majority of lease costs are reflected in the Consolidated Statement of Operations within Operations, product and technology and Sales, general and administrative expense. Other information related to leases was as follows (in thousands): Year Ended December 31, 2021 2020 Supplemental Cash Flows Information Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 5,401 $ 5,365 The following table discloses the weighted-average remaining lease term and discount rate for the period: December 31, 2021 December 31, 2020 Operating Leases Weighted average remaining lease term (years) 8.1 7.8 Weighted average discount rate 5.9 % 6.7 %

Long-term Debt and Convertible

Long-term Debt and Convertible Preferred Stock Warrants	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Long-term Debt and Convertible Preferred Stock Warrants	Long-term Debt and Convertible Preferred Stock Warrants The Company entered into a loan and security agreement (“Term Loan”) with Western Alliance Bank (“Bank”) for an aggregate amount up to $40.0 million to refinance its Loan and Security Agreement with Silicon Valley Bank (“SVB”) in February 2019. The Term Loan was amended three times before December 31, 2020. In February 2021, the Company amended and restated the loan and security agreement with the Bank to reflect all waivers and amendments to date. Subsequently, the Company borrowed an additional $5.0 million for an aggregate principal amount of $40.0 million. In connection with the additional $5.0 million draw, the Company issued additional warrant shares for Series E-1 preferred stock in the amount of 15,979. On May 14, 2021, the Company entered into the first amendment to the amended and restated loan and security Agreement (the “First Amendment”) with the Bank. The First Amendment amended the agreement dated February 3, 2021, with the most notable change being a decrease in interest rate. In accordance with the First Amendment, the interest rate on the Term Loan is the prime rate published in The Wall Street Journal plus 1.5% with a floor of 5.5% per annum. The Term Loan can be prepaid without penalty or premium at any time. The Term Loan contains certain covenants, which, if not met, allows the Bank to call all outstanding borrowings plus accrued interest. The covenants include minimum cash and liquidity thresholds, quarterly minimum net revenue and revenue growth thresholds, and a debt service requirement specified by the Term Loan. The Bank has secured the loan through its first ranking lien on all corporate assets, with a negative pledge on intellectual property. The Company was in compliance with all debt covenants as of December 31, 2021. As of December 31, 2021, the nominal interest rate was 5.50% and the effective interest rate was 6.65%. The maturities of the loan agreement as of December 31, 2021 are as follows (in thousands): Amount 2022 $ 8,000 2023 8,000 2024 20,000 Thereafter — Total future principal 36,000 Less: unamortized debt discount (673) Less: current portion of long-term debt (7,768) Non-current portion of long-term debt $ 27,559 Warrants Issued with Loan and Security Agreement The Company issued various preferred stock warrants under its loan and security agreements with SVB and the Bank. Immediately prior to the conversion upon IPO and as of December 31, 2020, the following preferred stock warrant liabilities were outstanding. Description Issuance Date Expiration Date Balance Sheet Classification Exercise Price Per Share Immediately Prior to the Completion of IPO December 31, 2020 Series D 1/22/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series D 4/20/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series E-1 2/7/2019 5/29/2030 Liability $ 6.2581 63,917 63,917 Series F 5/29/2020 5/29/2030 Liability $ 6.8839 10,376 10,376 Series E-1 8/14/2020 5/29/2030 Liability $ 6.2581 31,958 31,958 Series E-1 11/25/2020 5/29/2030 Liability $ 6.2581 15,979 15,979 Series E-1 2/8/2021 5/29/2030 Liability $ 6.2581 15,979 — 164,973 148,994 The convertible preferred stock warrant liability of $0.8 million was included in other non-current liabilities in the consolidated balance sheet as of December 31, 2020. Immediately prior to the completion of IPO in March 2021, all 164,973 shares of the convertible preferred stock warrant were remeasured to fair value and converted to equivalent number of Class B common stock warrants. The Company reclassified the convertible preferred stock warrant liability to additional paid-in capital upon the conversion. Refer to Note 10, Common Stock and Common Stock Warrants for more details on common stock warrants.

Common Stock and Common Stock W

Common Stock and Common Stock Warrants	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Common Stock and Common Stock Warrants	Common Stock and Common Stock Warrants Each share of Class A common stock is entitled to one vote per share. Each share of Class B common stock is entitled to ten votes per share and is convertible at any time into one share of Class A common stock. Immediately prior to the completion of the IPO, 65,970,938 shares of the convertible preferred stock converted to an equivalent number of shares of Class B common stock and 164,973 shares of the convertible preferred stock warrants were converted to an equivalent number of Class B common stock warrants. On August 2, 2021, the Company completed a follow‑on public offering of Class A common stock at a price of $24.25 per share. The Company issued and sold 2,000,000 shares of Class A common stock. The aggregate net proceeds were $45.5 million after deducting $3.3 million of underwriting discounts and commissions and offering costs. The selling stockholders sold 5,388,024 shares of Class A common stock (including 963,655 shares that were offered and sold pursuant to the full exercise of the underwriters’ option to purchase additional shares), which were converted from Class B common stock. The Company did not receive any of the proceeds from the sale of the Class A common stock by the selling stockholders. During the year ended December 31, 2021, the Company issued 128,643 shares of Class B common stock through cashless net exercises of the entire 164,973 shares underlying Class B common stock warrants. No Class B common stock warrants were outstanding as of December 31, 2021. The table below summarizes the Class A common stock and Class B common stock issued and outstanding: As of December 31, 2021 Authorized Issued and Outstanding (in thousands) Common stock Class A 1,000,000 57,779 Common stock Class B 120,000 40,656 Total common stock 1,120,000 98,435 The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows: As of December 31, 2021 2020 (in thousands) Outstanding stock options 19,440 22,775 Shares available for future grants 10,668 202 Employee stock plan purchases 2,917 — Restricted stock units outstanding 1,271 — Delayed share issuance related to acquisition 131 — Convertible preferred stock — 65,971 Outstanding convertible preferred stock warrants — 149 Total 34,427 89,097

Stock-Based Compensation Plans

Stock-Based Compensation Plans	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation Plans	Stock-Based Compensation Plans 2010 Stock Incentive Plan In 2010, the Company adopted the Second Amended and Restated 2010 Stock Plan (“2010 Plan”), and amended the 2010 Plan in 2011. The 2010 Plan provides for the grant of stock awards to employees, consultants and directors of the Company. Options granted under the 2010 Plan may either be Incentive Stock Options (“ISOs”) or Nonstatutory Stock Options (“NSOs”). ISOs may be granted to Company employees only, while stock awards other than ISOs may be granted to employees, directors and consultants. In 2020, the board of directors authorized an additional 6.5 million shares for the 2010 Plan. In 2021, the board of directors authorized an additional 1.0 million shares for the 2010 Plan. Stock awards under the 2010 Plan may be granted with terms of up to 10 years and at prices determined by the board of directors, provided, however, that (i) the exercise price of an ISO or NSO shall not be less than 100% of the estimated fair value of the shares on the date of the grant, and (ii) the exercise price of an ISO granted to a 10% or more stockholder shall not be less than 110% of the estimated fair value of the shares on the grant date. The options generally vest over a four-year period. For certain options, vesting accelerates upon the occurrence of specified events, such as a change of control. IPO Options Under the 2010 Plan In August 2020, the Company’s board of directors approved stock options for 3,588,535 common shares to be granted to certain officers and employees with an exercise price of $2.05 per share. 50% of the options granted vest over a four -year period commencing on the effective date of the IPO. The remaining 50% of the options granted vest over a four -year period commencing on the one -year anniversary of the IPO. As these stock options vest upon the satisfaction of both a time-based condition and a performance condition, the fair value of these stock options of $6.7 million, in aggregate, will be recognized as compensation expense over the requisite service period using the accelerated attribution method . In the year ended on December 31, 2021, $3.2 million was recognized as compensation expense from stock options subject to these performance conditions. 2021 Stock Option and Incentive Plan In February 2021, in connection with the IPO, the Company’s board of directors adopted the 2021 Stock Option and Incentive Plan (“2021 Plan”) to replace the 2010 Plan, which was subsequently approved by the Company’s stockholders in March 2021. The 2021 Plan became effective on March 24, 2021 . As of December 31, 2021, no stock options were granted under the 2021 Plan. As of December 31, 2021, 1,436,451 restricted stock units were granted under the 2021 Plan. Stock option activity under the 2010 Plan, as amended is as follows: Options Available for Grant (in thousands) Number of Options Outstanding Weighted-Average Exercise Price Per Share Weighted-Average Remaining Contractual Life (years) Aggregate Intrinsic Value (in thousands) Balances at December 31, 2020 202 22,775 $ 1.81 7.36 $ 107,696 Options authorized 1,000 — Options granted (924) 924 $ 6.54 Options exercised — (3,480) $ 1.51 Options forfeited and expired 172 (779) $ 2.57 Transferred to 2021 Plan (450) — Balances at December 31, 2021 — 19,440 $ 2.06 6.29 $ 208,042 Options outstanding and exercisable – December 31, 2021 11,434 $ 1.81 5.27 $ 125,242 The aggregated intrinsic value represents the difference between the exercise price and the fair value of common stock. The aggregate intrinsic value of all options exercised was $53.8 million, $2.9 million and $0.9 million during the years ended December 31, 2021, 2020 and 2019, respectively. The weighted average grant date fair value of options granted was $6.66, $1.72 and $1.38 during the years ended December 31, 2021, 2020 and 2019, respectively. The Company records stock-based awards at fair value as of the grant date, using the Black Scholes option pricing model. The fair value of stock options granted were estimated using the following range of assumptions: Year Ended December 31, 2021 (1) 2020 (1) 2019 Expected term (in years) 5.00 - 10.00 5.00-10.00 5.55 – 6.25 Expected volatility 59.4%-61.8% 46.9%-54.9% 45.5% – 47.8% Average risk-free rate 0.44%-1.10% 0.28%-1.55% 1.52% – 2.44% Dividend yield — — — ________________ (1) Assumptions include non-employee options after adoption of ASU 2018-07 as of January 1, 2020. Each of these inputs is subjective and generally requires significant judgment. Fair Value of Common Stock —Historically, for all periods prior to the IPO in March 2021, the fair value of the shares of common stock has historically been determined by the Company’s board of directors as there was no public market for the common stock. The board of directors determines the fair value of our common stock by considering a number of objective and subjective factors, including: the valuation of comparable companies, sales of preferred stock to unrelated third parties, our operating and financial performance, the lack of liquidity of common stock and general and industry specific economic outlook, amongst other factors. After the completion of the IPO in March 2021, the fair value of each share of underlying common stock is based on the closing price of the Company’s common stock as reported on the date of grant on the Nasdaq Global Select Market. Expected Term —The expected term represents the period that the Company’s stock options are expected to be outstanding and is determined using the simplified method (based on the mid-point between the vesting date and the end of the contractual term) as the Company has concluded that its stock option exercise history does not provide a reasonable basis upon which to estimate expected term. Volatility — Because the Company does not have sufficient trading history for its common stock, the expected volatility was estimated based on the average volatility for comparable publicly-traded companies, over a period equal to the expected term of the stock option grants. Risk-free Rate —The risk-free rate assumption is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of the option. Dividends —The Company has never paid dividends on its common stock and does not anticipate paying dividends on common stock. Therefore, the Company uses an expected dividend yield of zero. 2021 Employee Stock Purchase Plan In February 2021, the Company’s board of directors adopted the Employee Stock Purchase Plan (“ESPP”), which was subsequently approved by the stockholders in March 2021. The ESPP became effective on March 24, 2021. The first offering period began on March 25, 2021, and there was $0.5 million in stock-based compensation related to the ESPP for the year ended December 31, 2021. The Company used the following assumptions to estimate the fair value of stock offered under the ESPP for the years ended December 31, 2021: Year Ended December 31, 2021 Expected term (in years) 0.50 - 0.68 Expected volatility 60.65% - 71.25% Average risk-free rate 0.05% - 0.10% Dividend yield — Weighted average fair value of purchase rights $5.28 Restricted Stock Units The Company issues service-based and performance-based RSUs to employees. The RSUs automatically convert to shares of the Company’s common stock on a one-for-one basis as the awards vest. RSUs granted to newly hired employees typically vest 25% annually over 4 years commencing on the date of grant. The RSUs are measured at grant date fair value, at the market price of the Company’s common stock on the grant date. The Company records stock-based compensation expense related to the RSUs ratably over the employee respective requisite service period. The following table summarizes RSUs excluding RSUs with performance-based vesting conditions (“PSUs”) activity under the 2021 Plan: Shares (in thousands) Weighted-Average Grant-Date Fair Value Weighted-Average Remaining Contractual Life (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2020 — $ — Granted 1,405 $ 18.92 Vested (84) $ 20.21 Forfeited and cancelled (81) $ 19.83 Outstanding at December 31, 2021 1,240 1.77 $ 15,813 Stock-based Compensation Total stock-based compensation expense by department is as follows (in thousands): Year Ended December 31, 2021 2020 2019 Operations, product and technology $ 4,241 $ 3,739 $ 3,877 Marketing 1,405 1,067 1,018 Sales, general and administrative 7,313 2,530 2,783 Total stock-based compensation expense $ 12,959 $ 7,336 $ 7,678 Stock-based compensation costs capitalized as part of internal-use software was $0.3 million during the year ended December 31, 2021. No such costs were capitalized during the years ended December 31, 2020 and 2019. As of December 31, 2021, there was $11.9 million of total unrecognized stock-based compensation related to outstanding stock options, which will be recognized over a weighted average period of 1.85 years. As of December 31, 2021, the Company had $21.3 million unrecognized stock-based compensation related to RSUs excluding PSUs, which will be recognized over the weighted average remaining requisite service period of 3.37 years. The total fair value of RSUs excluding PSUs that vested for the years ended 2021 and 2020 was $1.7 million and zero, respectively. As of December 31, 2021, there was $0.3 million of total unrecognized stock-based compensation on ESPP, which will be recognized over a weighted average period of 0.4 years.

Commitment and Contingencies

Commitment and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Noncancellable Purchase Commitments As of December 31, 2021, the Company has non-cancelable contractual commitments of $17.0 million for software, construction and other services in the ordinary course of business with varying expiration terms through 2025. As of December 31, 2021, the future minimum payments under these arrangements were as follows (in thousands): Purchase Commitments 2022 $ 11,902 2023 3,134 2024 1,026 2025 939 2026 — Thereafter — Total future minimum payments $ 17,001 Legal Contingencies The Company is subject to litigation claims and assessments from time to time in the ordinary course of business. The Company’s management does not believe that any such matters, individually or in the aggregate, will have a material adverse effect on the Company’s business, financial condition, results of operations or cash flows. Indemnifications

Retirement Plan

Retirement Plan	12 Months Ended
	Dec. 31, 2021
Retirement Benefits [Abstract]
Retirement Plan	Retirement PlanIn 2010, the Company sponsored a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”). The 401(k) Plan covers all United States employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pretax basis. For the years ended December 31, 2021, 2020 and 2019, no employer contributions were made to the 401(k) Plan.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income TaxesThe Company had no federal or foreign provision for income taxes as the Company has incurred operating losses since inception. The Company has U.S. pre-tax book loss of $61.9 million and foreign pre-tax book loss of $1.2 million for the year ended December 31, 2021. The Company’s state tax provision, which was current, was $80,000 and $56,000 for the years ended December 31, 2021 and 2020, respectively. The Company’s effective tax rate, as a percentage of pretax income, differs from the statutory federal rate primarily due to the valuation allowance that the Company records on its deferred tax assets as management believes it is more likely than not that the deferred tax assets will not be fully realized. The reconciliation of the federal statutory income tax provision for the Company’s effective income tax provision (in thousands): Year Ended December 31, 2021 2020 Tax at federal statutory rate $ (13,250) $ (10,042) State taxes, net of federal effect 63 42 Non-deductible expenses 156 67 Foreign tax rate differential 259 — Stock based compensation (3,086) 1,077 Change in valuation allowance 15,712 8,814 Other 226 98 Provision for income taxes $ 80 $ 56 The significant components of the Company’s deferred tax assets and liabilities consisted of (in thousands): December 31, 2021 2020 Deferred tax assets: Accruals and reserves $ 2,043 $ 2,472 Inventory and deferred revenue 770 690 Stock compensation 2,128 1,151 Other 1,417 670 Net operating loss carryforwards 75,804 53,550 Gross deferred tax assets 82,162 58,533 Less: valuation allowance (75,348) (56,581) Total deferred tax assets 6,814 1,952 Deferred tax liabilities: Fixed assets (4,876) (1,952) Intangibles (1,938) — Gross deferred tax liabilities (6,814) (1,952) Net deferred tax assets $ — $ — Deferred income taxes reflect the net tax effects of (a) temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes, and (b) operating losses and tax credit carryforwards. Net deferred tax assets consist primarily of net operating losses of approximately $75.8 million as of December 31, 2021 and $53.6 million as of 2020 related to U.S. federal and state taxes. A valuation allowance is provided when it is more likely than not that the deferred tax assets will not be realized. The Company has established a valuation allowance to offset deferred tax assets as of December 31, 2021 and 2020 due to the uncertainty of realizing future benefits from its net operating loss carryforwards and other deferred tax assets. The valuation allowance increased by approximately $18.8 million and $10.5 million in the years ended December 31, 2021 and 2020, respectively. Federal and state, and foreign net operating loss carryforwards of approximately $297.7 million, $203.2 million and $12.0 million, respectively, for income tax purposes are available to offset future taxable income as of December 31, 2021. $189.4 million of the U.S. federal net operating losses can be carried forward indefinitely and are available to offset 80% of future taxable income. If not used, these carryforwards will begin to expire in varying amounts beginning in 2030. The Tax Reform Act of 1986 and similar California legislation impose substantial restrictions on the utilization of net operating losses and tax credit carryforwards in the event that there is a change in ownership as provided by Section 382 and Section 383 of the Internal Revenue Code and similar state provisions. Such a limitation could result in the limitation and/or expiration of the net operating loss carryforwards and tax credits before utilization, which could result in increased future tax liabilities when the Company becomes taxable for federal or state purposes. While the Company has experienced an ownership change since its inception, an immaterial amount of net operating losses or tax credits has been limited as of December 31, 2021. The Company has no uncertain tax positions, and the Company’s policy is to recognize interest expense and penalties related to income tax matters as a component of income tax expense. There was no accrued interest and penalties associated with uncertain tax positions as of December 31, 2021 and 2020. The Company’s tax years 2010 through current will remain open for examination by the federal and state authorities for three and four years, respectively, from the date of utilization of any net operating loss credits. The Company is not currently under examination by income tax authorities in federal, state or other jurisdictions.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	Net Loss Per Share Attributable to Common Stockholders The following participating securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented, because including them would have been anti-dilutive (on an as-converted basis): As of December 31, 2021 2020 2019 (in thousands) Outstanding stock options 19,440 22,775 17,985 Restricted stock units 1,271 — — Delayed share issuance related to acquisition 130 — — Employee stock purchase plan 17 — — Convertible preferred stock — 65,971 65,928 Outstanding convertible preferred stock warrants — 149 171 Total 20,858 88,895 84,084

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany account balances and transactions have been eliminated upon consolidation.
Use of Estimates	The preparation of consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the amounts that are reported in the consolidated financial statements and the related disclosures. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include, but are not limited to, the useful lives of property and equipment and intangibles, allowance for sales returns, allowance for bad debts, breakage on loyalty points and rewards, valuation of inventory, warrants, stock-based compensation, valuation of right-of-use assets, valuation of goodwill and acquired intangibles and income taxes.
Foreign Currency	The Company’s functional currency is the United States (“U.S.”) dollar for its operations except for Remix whose functional currency is the Bulgarian lev. In accordance with authoritative guidance, assets and liabilities of the Company’s foreign operations are translated from the respective functional currencies into U.S. dollars at period-end rates, while income and expenses are translated using the average exchange rate during the period in which the transactions occurred. The related translation adjustments are reflected as a foreign currency translation adjustment in accumulated other comprehensive income (loss).
Revenue Recognition, Gift Cards and Site and Seller Credits	Revenue is recognized in accordance with Accounting Standards Topic 606 (“ASC 606”). Under ASC 606, revenue is recognized upon transfer of control of promised goods and services to customers in an amount that reflects the consideration the Company expects to receive for those goods and services. The Company generates the majority of its revenue from its marketplace, which allows its buyers to browse and purchase resale items for women’s and kids’ apparel, shoes and accessories on behalf of sellers. The Company recognizes revenue through the following steps: (1) identification of the contract, or contracts, with the customer; (2) identification of the performance obligations in the contract; (3) determination of the transaction price; (4) allocation of the transaction price to the performance obligations in the contract; and (5) recognition of revenue when, or as, it satisfies a performance obligation. Both buyers and sellers may be customers in the Company’s revenue arrangements. Sellers are the primary customer in a consignment arrangement while the buyer is the primary customer in sale of Company-owned inventory, referred to as product sales. A contract with a customer exists in both cases when the end-customer purchases the goods obligating the Company to deliver the identified performance obligation(s). Generally, the Company requires authorization from a credit card or other payment method (such as PayPal), or verification of receipt of payment, before the products are shipped to buyers. The Company generally receives payments from buyers before payments to the sellers are due. Consignment Revenue The Company generates consignment revenue from the sale of secondhand women’s and kids’ apparel, shoes and accessories on behalf of sellers. The Company retains a percentage of the proceeds received as payment for its consignment service. The Company reports consignment revenue on a net basis as an agent and not the gross amount collected from the buyer. Title to the consigned goods remain with the consignor until transferred to the buyer, which occurs subsequent to purchase of the consigned goods and upon expiration of the allotted return period. The Company does not take title of consigned goods at any time except in certain cases where the consignment window expires or returned goods become Company-owned inventory. Consignment revenue is recognized upon purchase of the consigned good by the buyer as its performance obligation of providing consignment services to the consignor is satisfied at that point. Consignment revenue is recognized net of seller payouts, discounts, incentives and returns. Sales tax assessed by governmental authorities is excluded from revenue. Product Revenue The Company recognizes product revenue on a gross basis as the Company acts as the principal in the transaction. Online sales and sales to third-party retail partners are generally recognized upon shipment of the purchased good to the buyer. Product revenue is recognized net of discounts, incentives and returns. Sales tax assessed by governmental authorities is excluded from revenue. Shipping Fees The Company charges shipping fees to buyers, which are included in revenue. All outbound shipping costs are accounted for in cost of revenue at the time revenue is recognized. Returns The Company generally has a 14-day return period which may change from time to time and recognizes a returns reserve, based on historical experience, which is recorded in accrued and other current liabilities on the consolidated balance sheet. Incentives Incentives include website discounts, customer credits and loyalty program rewards issued to sellers and buyers. Incentives are treated as a reduction of product revenue and consignment revenue. Revenue treatment for our loyalty program is discussed further below under Deferred Revenue. Deferred Revenue Deferred revenue consists primarily of cash collections for product items purchased, but not shipped, and revenue allocated to unredeemed loyalty points. Cash collections for items purchased, but not shipped, are generally recognized as revenue upon shipment. As of December 31, 2021 and 2020, the Company had $1.7 million and $0.9 million, respectively, in deferred revenue for such items, which were recognized shortly after the period end, and are included in accrued and other current liabilities on the consolidated balance sheets. In August 2019, the Company launched a customer loyalty program that provides customers with rewards that can be applied to future purchases or other incentives. Loyalty points and rewards are accounted for as separate performance obligations and accrued as deferred revenue in the amount of the transaction price allocated to the points and rewards. The allocated transaction price is based on the estimated fair value per point, net of breakage. Breakage is estimated based on the Company’s historical redemption rates. Revenue is recognized when the loyalty rewards are redeemed or expire. As of December 31, 2021 and 2020, the Company had a liability of $4.0 million and $4.1 million, respectively, related to the loyalty program which is included in accrued and other current liabilities in the consolidated balance sheets. The Company recognized $13.8 million, $6.6 million and $0.1 million of revenue related to loyalty points in the 2021, 2020 and 2019 periods, respectively. Revenue allocated to loyalty points is expected to be recognized within one year as loyalty points expire 12 months after issuance. Revenue by Geographic Area
Segments	The Company operates under one operating segment and one reportable segment as its chief operating decision maker, who is its Chief Executive Officer, reviews financial information presented on a consolidated basis for purposes of making operating decisions, allocating resources and evaluating financial performance.
Business Combinations	The Company accounts for business combinations using the acquisition method of accounting, which requires, among other things, allocation of the fair value of purchase consideration to the tangible and intangible assets acquired and liabilities assumed at estimated fair values on the acquisition date. The excess of the fair value of purchase consideration over the values of these identifiable assets and liabilities is recorded as goodwill. When determining the fair value of assets acquired and liabilities assumed, the management makes significant estimates and assumptions, especially with respect to intangible assets. Significant estimates in valuing intangible assets include, but are not limited to, expected future cash flows, which includes consideration of future growth and margins, future changes in technology, brand awareness and discount rates. Fair value estimates are based on the assumptions that management believes to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. After the purchase accounting is finalized, any subsequent adjustments are reflected in the consolidated statements of operations. Acquisition costs, such as legal and consulting fees, are expensed as incurred.
Net Loss Per Share Attributable to Common Stockholders	The Company follows the two-class method when computing net loss per common share when shares issued meet the definition of participating securities. The two-class method determines net loss per share for each class of common stock and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income available to stockholders for the period to be allocated between common stock and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed. The Company’s convertible preferred stock contractually entitles the holders of such shares to participate in dividends but does not contractually require the holders of such shares to participate in the Company’s losses. The rights, including the liquidation and dividend rights and sharing of losses, of the Class A common stock and Class B common stock are identical, other than voting rights. As the liquidation and dividend rights and sharing of losses are identical, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share attributed to common stockholders will, therefore, be the same for both Class A and Class B common stock on an individual or combined basis.
Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents	The Company classifies all highly liquid instruments with an original maturity of three months or less at the time of purchase as cash equivalents. Cash and cash equivalents are comprised of bank deposits and commercial paper, and money market funds. Restricted cash primarily represents letters of credit with financial institutions held as collateral for its facility leases. Restricted cash is classified non-current if the Company expects that the cash will remain restricted for a period greater than one-year. Current restricted cash is included in other current assets on the consolidated balance sheet.
Marketable Securities	The Company invests its excess cash in investment grade, short to intermediate-term, fixed income securities and recognizes the transaction on the trade-date. The Company’s marketable securities are classified as available-for-sale in current assets because they represent investments of cash available for current operations. Marketable securities are reported at fair value with unrealized gains and losses reported, net of tax, as a separate component of accumulated other comprehensive gain (loss) until realized. The marketable securities are reviewed periodically to identify possible other-than-temporary impairments. Realized gains or losses and other-than-temporary impairments, if any, on available-for sale securities are reported in other income, net as incurred.
Concentrations of Credit Risk	Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents, marketable securities and accounts receivable. The Company deposits cash at major financial institutions, and at times, such cash may exceed federally insured limits. The credit risk is believed to be minimal due to the financial position of the depository institutions in which those deposits are held. The Company has never experienced any losses on deposits since inception. The Company’s investment policy restricts cash investments to highly liquid, short to intermediate-term, high grade fixed income securities, and as a result, the Company believes its cash equivalents and marketable securities represent minimal credit risk.
Accounts Receivable, Net	Accounts receivable consists of amounts due from payment processors and trade customers that do not bear interest. The Company records an allowance for doubtful accounts for estimated losses inherent in its trade accounts receivable portfolio. In establishing the required allowance, management considers historical losses adjusted for current market conditions, the financial condition of the customer, the amount of receivables in dispute, and the current receivables aging and payment patterns. The Company does not have any off-balance sheet credit exposure related to its customers.
Inventory, Net	Inventories, consisting of merchandise that the Company has purchased and holds title, are accounted for using the specific identification method, and are valued at the lower of cost and net realizable value. The cost of inventory is equal to the cost of the merchandise paid to the seller and related inbound shipping costs. Inventory valuation requires the Company to make judgments based on currently available information about the likely method of disposition, such as through sales to individual customers or liquidations, and expected recoverable values of each disposition category. The Company records an inventory write-down based on the age of the inventory and historical experience of expected sell-through.
Property and Equipment, Net	Property and equipment are stated at cost less accumulated depreciation. Depreciation is recorded on a straight-line basis over the estimated useful lives of the assets. Maintenance and repairs are charged to expense as incurred, and improvements and betterments are capitalized. When assets are retired or otherwise disposed of, the cost and accumulated depreciation and amortization are removed from the balance sheet and any resulting gain or loss is reflected in the consolidated statement of operations in the period realized.
Internal-Use Software	The Company capitalizes qualifying proprietary software development costs that are incurred during the application development stage. Capitalization of costs begins when two criteria are met: (i) the preliminary project stage is completed, and (ii) it is probable that the software will be completed and placed in service for its intended use. Capitalization ceases when the software is substantially complete and ready for its intended use including the completion of all significant testing. Costs related to preliminary project activities and post implementation operating activities are expensed as incurred.
Impairment of Long-Lived Assets	The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset group may not be recoverable. Recoverability of assets held and used is measured by comparison of the carrying amount of an asset to the future undiscounted cash flows expected to be generated from the use of the asset and its eventual disposition. If such assets are considered to be impaired, the impairment to be recognized is equal to the excess of the fair value over the carrying amount of the impaired assets.
Goodwill	Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in a business combination. Goodwill is not subject to amortization, but is reviewed for impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying value of goodwill may not be recoverable.
Acquired Intangible Assets	When a business is acquired, a portion of the purchase price is typically allocated to identifiable intangible assets, such as trademark, acquired technology and customer relationships. Fair value of these assets is determined primarily using the income approach, which requires the management to project future cash flows and apply an appropriate discount rate. Intangible assets with finite lives are amortized on a straight-line basis over their economic lives ranging from 3 years to 9 years. Estimates are based upon assumptions believed to be reasonable but which are inherently uncertain and unpredictable. Assumptions may be incomplete or inaccurate, and unanticipated events and circumstances may occur. Incorrect estimates could result in future impairment charges, and those charges could be material to the Company’s results of operations.
Investments	The Company made a strategic investment in preferred shares of a privately held online retail company in October 2021. The Company accounts for its investment in accordance with ASC 321 , Investments – Equity Securities
Asset Retirement Obligations	The Company records asset retirement obligations (“AROs”) for the estimated cost of restoring its automated warehouse facilities to the specific condition required per the terms of its lease agreement, upon termination of the lease. AROs represent the present value of the expected costs and timing of the related obligations incurred. The ARO assets and liabilities are recorded in property and equipment within the machinery and equipment line item and other non-current liabilities in the consolidated balance sheets. The Company records accretion expense, which represents the increase in the ARO, over the remaining estimated duration of the lease including renewal periods that are included in the lease life. Accretion expense is recorded in operations, product and technology expense in the consolidated statement of operations using accretion rates based on credit adjusted risk-free interest rates.
Leases	Effective January 1, 2020, the Company adopted ASC 842, Leases (“ASC 842”), using the optional transition method and applied the standard only to leases that existed at that date. Under ASC 842, the Company determines if an arrangement is or contains a lease at inception by assessing whether the arrangement contains an identified asset and whether it has the right to control the identified asset. Lessees are required to classify leases as either finance or operating leases and to record a right-of-use (“ROU”) asset and a lease liability for all leases with a term greater than 12 months regardless of the lease classification. The lease classification will determine whether the lease expense is recognized based on an effective interest rate method or on a straight-line basis over the term of the lease. The Company determines the initial classification and measurement of its ROU assets and lease liabilities at the lease commencement date and thereafter if modified. ROU assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Lease liabilities are recognized at the lease commencement date based on the present value of future lease payments over the lease term. ROU assets are based on the measurement of the lease liability and also include any lease payments made prior to or on lease commencement and exclude lease incentives and initial direct costs incurred, as applicable. As the implicit rate in the Company's leases is generally unknown, the Company uses its incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future lease payments. The Company gives consideration to its existing credit arrangements, term of the lease, total lease payments and adjust for the impacts of collateral, as necessary, when calculating its incremental borrowing rates. The lease terms may include options to extend or terminate the lease when it is reasonably certain the Company will exercise any such options. Lease costs for the Company's operating leases are recognized on a straight-line basis within operating expenses over the lease term.
Seller Payable	Seller payable includes amounts owed to sellers upon the purchase of sellers’ goods by the Company or by buyers. Amounts are initially provided as a credit to sellers. These credits may be applied towards purchases from the Company, converted to third-party retailer or thredUP gift cards or redeemed for cash.
Income Taxes	Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income on the years in which those temporary differences are expected to be recovered and settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company records interest and penalties related to unrecognized tax benefits in income tax expense.
Cost of Revenue	Cost of consignment revenue consists of outbound shipping, outbound labor and packaging costs. Cost of product revenue mainly consists of the inventory cost, inbound shipping related to the sold merchandise, outbound shipping, outbound labor, packaging costs and inventory write-downs.
Operations, Product and Technology	Operations, product and technology expenses consist primarily of distribution center operating costs and product and technology expenses. Distribution center operating costs include personnel costs, distribution center rent, maintenance and equipment depreciation as well as inbound shipping costs, other than those capitalized in inventory. Product and technology costs include personnel costs for the design and development of product and the related technology that is used to operate the distribution centers, merchandise science, website development and related expenses for these departments. Operations, product and technology expenses also include an allocation of corporate facilities and information technology costs including equipment, depreciation and rent.
Marketing	Marketing costs consist primarily of advertising, public relations expenditures and personnel costs for employees engaged in marketing. Marketing costs also include an allocation of corporate facilities and information technology costs including equipment, depreciation and rent.
Sales, General and Administrative	Sales, general and administrative expenses consist of personnel costs for employees involved in general corporate functions, including accounting, finance, tax, legal and people services; customer service; and retail stores. Sales, general and administrative also includes payment processing fees, professional fees and allocation of corporate facilities and information technology costs such as equipment, depreciation and rent.
Stock-Based Compensation	Stock-based compensation costs are based on the fair values on the date of grant for stock awards and stock options and on the date of enrollment for the employee stock purchase plan (“ESPP”). The fair values of Restricted Stock Units (“RSUs”) are based on ThredUp’s stock price on the date of grant. The fair values of stock options and ESPP are estimated using the Black-Scholes option-pricing model. The fair values of equity awards are recognized as compensation expense over the requisite service period or over the period in which the related services are received (generally the vesting period), using the straight-line method. The estimated fair value of equity awards that contain performance conditions is expensed over the term of the award once the Company has determined that it is probable that performance conditions will be satisfied. The Company accounts for forfeitures as they occur. The determination of fair value for share-based awards on the date of grant using an option pricing model requires management to make certain assumptions regarding subjective variables.
Prior Period Reclassifications	Within the consolidated balance sheets, the Company included restricted cash, non-current within non-current other assets for the prior period to conform with current period presentation.
New Accounting Pronouncements Recently Issue But Not Yet Adopted	In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments
Fair Value Measurement	The Company’s money market funds and commercial paper were included within cash equivalents. U.S. treasury securities, U.S. government agency bonds and corporate debt securities were included within the marketable securities. The Company’s money market funds, U.S. treasury securities, corporate debt securities, U.S. government agency bonds were valued using Level 1 inputs because they are valued using quoted market prices. The Company’s commercial papers were valued using Level 2 inputs because they are valued using quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Revenue by Geographic Area	The following summarizes the Company’s revenue by geographic area (in thousands): Year Ended December 31, 2021 December 31, 2020 December 31, 2019 North America $ 240,677 $ 186,015 $ 163,812 Europe 11,115 — — Total $ 251,792 $ 186,015 $ 163,812
Schedule of Cash and Cash Equivalents	The following table provides a reconciliation of cash and cash equivalents as well as restricted cash reported within the consolidated balance sheets to the amounts shown in the consolidated statements of cash flows (in thousands): December 31, 2021 2020 Cash and cash equivalents $ 84,550 $ 64,485 Restricted cash, current 560 364 Restricted cash, non-current 6,730 2,690 Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows $ 91,840 $ 67,539
Restrictions on Cash and Cash Equivalents	The following table provides a reconciliation of cash and cash equivalents as well as restricted cash reported within the consolidated balance sheets to the amounts shown in the consolidated statements of cash flows (in thousands): December 31, 2021 2020 Cash and cash equivalents $ 84,550 $ 64,485 Restricted cash, current 560 364 Restricted cash, non-current 6,730 2,690 Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows $ 91,840 $ 67,539
Schedule of Property and Equipment, Net	The estimated useful lives of the Company’s property and equipment are as follows: Machinery and equipment 3-10 years Internal-use software 1-3 years Leasehold improvements Shorter of lease term or estimated useful life Computers and software 2-3 years Furniture and fixtures 5-7 years Property and equipment, net consists of the following (in thousands): December 31, 2021 2020 Machinery and equipment $ 48,874 $ 35,254 Internal-use software 5,517 4,764 Computers and software 5,336 3,677 Leasehold improvements 4,705 4,459 Furniture and fixtures 856 519 Construction in progress 10,740 6,548 76,028 55,221 Less: accumulated depreciation and amortization (20,562) (14,090) Property and equipment, net $ 55,466 $ 41,131

Financial Instruments and Fai_2

Financial Instruments and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Financial Instruments Measured at Fair Value	The following table provides the financial instruments measured at fair value for each of the respective periods (in thousands): Fair Value as of December 31, 2021 Level 1 Level 2 Level 3 Total Assets Money market fund $ 41,376 $ — $ — $ 41,376 U.S. treasury securities 37,190 — — 37,190 Commercial paper — 12,098 — 12,098 Corporate debt securities 55,921 — — 55,921 U.S. government agency bonds 28,166 — — 28,166 Total $ 162,653 $ 12,098 $ — $ 174,751 Classified as: Cash equivalents $ 53,474 Marketable securities 121,277 $ 174,751 December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 43,460 $ — $ — $ 43,460 Total cash equivalents $ 43,460 $ — $ — $ 43,460 Liabilities Convertible preferred stock warrant liability $ — $ — $ 805 $ 805 Total liabilities $ — $ — $ 805 $ 805

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment, Net	The estimated useful lives of the Company’s property and equipment are as follows: Machinery and equipment 3-10 years Internal-use software 1-3 years Leasehold improvements Shorter of lease term or estimated useful life Computers and software 2-3 years Furniture and fixtures 5-7 years Property and equipment, net consists of the following (in thousands): December 31, 2021 2020 Machinery and equipment $ 48,874 $ 35,254 Internal-use software 5,517 4,764 Computers and software 5,336 3,677 Leasehold improvements 4,705 4,459 Furniture and fixtures 856 519 Construction in progress 10,740 6,548 76,028 55,221 Less: accumulated depreciation and amortization (20,562) (14,090) Property and equipment, net $ 55,466 $ 41,131

Acquisition of Remix (Tables)

Acquisition of Remix (Tables)	12 Months Ended
	Dec. 31, 2021
Business Combination and Asset Acquisition [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The allocation of the purchase price is based on the estimated fair values of the assets acquired and liabilities assumed by major class related to the acquisition of Remix and are reflected, as of the acquisition date, in the accompanying financial statements as follows (in thousands): Purchase Price Cash consideration $ 25,550 Delayed share issuance 2,744 Total purchase consideration $ 28,294 Cash and cash equivalents 1,860 Accounts receivable 1,150 Inventory 3,657 Intangible assets 14,800 Other assets 786 Accounts payable (3,102) Accrued and other liabilities (3,356) Total net assets acquired 15,795 Goodwill as of October 7, 2021 $ 12,499 Foreign currency translation adjustments (261) Goodwill as of December 31, 2021 $ 12,238
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	Intangible assets with determinable lives Customer relationships $ 5,200 Developed technology 4,900 Trademarks 4,700 Total identified intangible assets as of October 7, 2021 $ 14,800 Foreign currency translation adjustments (308) Gross carrying amount as of December 31, 2021 $ 14,492

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	The gross carrying amounts and accumulated amortization of the intangible assets with determinable lives are as follows (in thousands): As of December 31, 2021 Intangible assets with determinable lives Amortization Period (years) Gross carrying amount Accumulated Carrying amount, net Customer relationships 8 $ 5,092 $ (150) $ 4,942 Developed technology 3 4,798 (373) 4,425 Trademarks 9 4,602 (115) 4,487 Total $ 14,492 $ (638) $ 13,854

Balance Sheet Components (Table

Balance Sheet Components (Tables)	12 Months Ended
	Dec. 31, 2021
Balance Sheet Components [Abstract]
Schedule of Inventories	Inventories consist of the following (in thousands): December 31, 2021 2020 Raw materials $ 908 $ — Work in progress 670 — Finished goods 8,247 3,519 $ 9,825 $ 3,519
Schedule of Other Current Liabilities	Accrued and other current liabilities consist of the following (in thousands): December 31, 2021 2020 Gift card and site credit liabilities $ 13,223 $ 9,362 Accrued compensation 6,438 3,443 Accrued vendor liabilities 6,031 3,407 Deferred revenue 5,878 5,094 Accrued taxes 5,728 4,594 Allowance for returns 6,209 3,389 Accrued other 1,746 3,252 $ 45,253 $ 32,541

Lease Agreements (Tables)

Lease Agreements (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Maturities of Operating Lease Liabilities	The following table summarizes maturities of the Company’s operating lease liabilities as of December 31, 2021 (in thousands): December 31, 2022 $ 7,931 2023 7,808 2024 6,930 2025 6,061 2026 5,706 Thereafter 26,437 Total lease payments 60,873 Less: imputed interest (13,843) Less: tenant improvement allowance yet to be received (6,102) Total lease liabilities 40,928 Less: current lease liabilities (3,931) Total non-current lease liabilities $ 36,997
Supplemental Cash Flow Information	The following table summarizes the cost components of the Company’s operating leases (in thousands): Year Ended December 31, 2021 2020 Operating Lease Cost Fixed Cost $ 5,591 $ 5,568 Short-Term Lease Cost 7 58 Variable Lease Cost (1) 1,381 1,197 Total Operating Lease Cost (2) $ 6,979 $ 6,823 ________________ (1) Under the terms of the lease agreements, the Company is also responsible for certain variable lease payments that are not included in the measurement of the lease liability. Variable lease payments include non-lease components such as common area maintenance fees. (2) The majority of lease costs are reflected in the Consolidated Statement of Operations within Operations, product and technology and Sales, general and administrative expense. Other information related to leases was as follows (in thousands): Year Ended December 31, 2021 2020 Supplemental Cash Flows Information Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 5,401 $ 5,365 The following table discloses the weighted-average remaining lease term and discount rate for the period: December 31, 2021 December 31, 2020 Operating Leases Weighted average remaining lease term (years) 8.1 7.8 Weighted average discount rate 5.9 % 6.7 %

Long-term Debt and Convertibl_2

Long-term Debt and Convertible Preferred Stock Warrants (Tables)	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Schedule of Maturities of Debt	The maturities of the loan agreement as of December 31, 2021 are as follows (in thousands): Amount 2022 $ 8,000 2023 8,000 2024 20,000 Thereafter — Total future principal 36,000 Less: unamortized debt discount (673) Less: current portion of long-term debt (7,768) Non-current portion of long-term debt $ 27,559
Schedule of Warrants Issued	Description Issuance Date Expiration Date Balance Sheet Classification Exercise Price Per Share Immediately Prior to the Completion of IPO December 31, 2020 Series D 1/22/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series D 4/20/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series E-1 2/7/2019 5/29/2030 Liability $ 6.2581 63,917 63,917 Series F 5/29/2020 5/29/2030 Liability $ 6.8839 10,376 10,376 Series E-1 8/14/2020 5/29/2030 Liability $ 6.2581 31,958 31,958 Series E-1 11/25/2020 5/29/2030 Liability $ 6.2581 15,979 15,979 Series E-1 2/8/2021 5/29/2030 Liability $ 6.2581 15,979 — 164,973 148,994

Common Stock and Common Stock_2

Common Stock and Common Stock Warrants (Tables)	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Schedule of Common Stock Issued and Outstanding	The table below summarizes the Class A common stock and Class B common stock issued and outstanding: As of December 31, 2021 Authorized Issued and Outstanding (in thousands) Common stock Class A 1,000,000 57,779 Common stock Class B 120,000 40,656 Total common stock 1,120,000 98,435 The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows: As of December 31, 2021 2020 (in thousands) Outstanding stock options 19,440 22,775 Shares available for future grants 10,668 202 Employee stock plan purchases 2,917 — Restricted stock units outstanding 1,271 — Delayed share issuance related to acquisition 131 — Convertible preferred stock — 65,971 Outstanding convertible preferred stock warrants — 149 Total 34,427 89,097

Stock-Based Compensation Plans

Stock-Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Stock Option Activity	Stock option activity under the 2010 Plan, as amended is as follows: Options Available for Grant (in thousands) Number of Options Outstanding Weighted-Average Exercise Price Per Share Weighted-Average Remaining Contractual Life (years) Aggregate Intrinsic Value (in thousands) Balances at December 31, 2020 202 22,775 $ 1.81 7.36 $ 107,696 Options authorized 1,000 — Options granted (924) 924 $ 6.54 Options exercised — (3,480) $ 1.51 Options forfeited and expired 172 (779) $ 2.57 Transferred to 2021 Plan (450) — Balances at December 31, 2021 — 19,440 $ 2.06 6.29 $ 208,042 Options outstanding and exercisable – December 31, 2021 11,434 $ 1.81 5.27 $ 125,242
Schedule of Fair Value Assumptions	The fair value of stock options granted were estimated using the following range of assumptions: Year Ended December 31, 2021 (1) 2020 (1) 2019 Expected term (in years) 5.00 - 10.00 5.00-10.00 5.55 – 6.25 Expected volatility 59.4%-61.8% 46.9%-54.9% 45.5% – 47.8% Average risk-free rate 0.44%-1.10% 0.28%-1.55% 1.52% – 2.44% Dividend yield — — — ________________
Schedule of Restricted Stock Unit Activity	The following table summarizes RSUs excluding RSUs with performance-based vesting conditions (“PSUs”) activity under the 2021 Plan: Shares (in thousands) Weighted-Average Grant-Date Fair Value Weighted-Average Remaining Contractual Life (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2020 — $ — Granted 1,405 $ 18.92 Vested (84) $ 20.21 Forfeited and cancelled (81) $ 19.83 Outstanding at December 31, 2021 1,240 1.77 $ 15,813
Schedule of ESPP Valuation Assumptions	The Company used the following assumptions to estimate the fair value of stock offered under the ESPP for the years ended December 31, 2021: Year Ended December 31, 2021 Expected term (in years) 0.50 - 0.68 Expected volatility 60.65% - 71.25% Average risk-free rate 0.05% - 0.10% Dividend yield — Weighted average fair value of purchase rights $5.28
Schedule of Stock-based Compensation Expense	Total stock-based compensation expense by department is as follows (in thousands): Year Ended December 31, 2021 2020 2019 Operations, product and technology $ 4,241 $ 3,739 $ 3,877 Marketing 1,405 1,067 1,018 Sales, general and administrative 7,313 2,530 2,783 Total stock-based compensation expense $ 12,959 $ 7,336 $ 7,678

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Payments	As of December 31, 2021, the future minimum payments under these arrangements were as follows (in thousands): Purchase Commitments 2022 $ 11,902 2023 3,134 2024 1,026 2025 939 2026 — Thereafter — Total future minimum payments $ 17,001

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	The reconciliation of the federal statutory income tax provision for the Company’s effective income tax provision (in thousands): Year Ended December 31, 2021 2020 Tax at federal statutory rate $ (13,250) $ (10,042) State taxes, net of federal effect 63 42 Non-deductible expenses 156 67 Foreign tax rate differential 259 — Stock based compensation (3,086) 1,077 Change in valuation allowance 15,712 8,814 Other 226 98 Provision for income taxes $ 80 $ 56
Schedule of Deferred Tax Assets and Liabilities	The significant components of the Company’s deferred tax assets and liabilities consisted of (in thousands): December 31, 2021 2020 Deferred tax assets: Accruals and reserves $ 2,043 $ 2,472 Inventory and deferred revenue 770 690 Stock compensation 2,128 1,151 Other 1,417 670 Net operating loss carryforwards 75,804 53,550 Gross deferred tax assets 82,162 58,533 Less: valuation allowance (75,348) (56,581) Total deferred tax assets 6,814 1,952 Deferred tax liabilities: Fixed assets (4,876) (1,952) Intangibles (1,938) — Gross deferred tax liabilities (6,814) (1,952) Net deferred tax assets $ — $ —

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Stockholders (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Participating Securities Excluded From the Computation of Diluted Net Loss Per Share	The following participating securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented, because including them would have been anti-dilutive (on an as-converted basis): As of December 31, 2021 2020 2019 (in thousands) Outstanding stock options 19,440 22,775 17,985 Restricted stock units 1,271 — — Delayed share issuance related to acquisition 130 — — Employee stock purchase plan 17 — — Convertible preferred stock — 65,971 65,928 Outstanding convertible preferred stock warrants — 149 171 Total 20,858 88,895 84,084

Organization and Description _2

Organization and Description of Business (Details) - USD ($) $ / shares in Units, $ in Thousands	Aug. 02, 2021	Mar. 26, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 25, 2021
Class of Stock [Line Items]
Price per share of common stock (in dollars per share)	$ 24.25
Aggregate net proceeds	$ 45,500
Payment of costs for the initial public offering		$ 17,700
Common stock, shares authorized (in shares)			1,120,000,000	110,000,000
Shares authorized (in shares)		100,000,000	100,000,000	68,140,000
Warrants outstanding (in shares)				148,994		164,973
Payments of stock issuance costs	$ 3,300		$ 4,729	$ 1,117	$ 0
Class B Common Stock Warrant
Class of Stock [Line Items]
Warrants outstanding (in shares)		164,973	0			164,973
Common Stock
Class of Stock [Line Items]
Stock converted (in shares)		65,970,938	65,971,000
Conversion of stock (in shares)		12,889,760
Common stock Class A
Class of Stock [Line Items]
Shares sold (in shares)	2,000,000
Common stock, shares authorized (in shares)		1,000,000,000	1,000,000,000
Common stock Class B
Class of Stock [Line Items]
Common stock, shares authorized (in shares)		120,000,000	120,000,000
Stock converted (in shares)			164,973
IPO
Class of Stock [Line Items]
Shares sold (in shares)		13,800,000
Price per share of common stock (in dollars per share)		$ 14
Aggregate net proceeds		$ 175,500

Significant Accounting Polici_4

Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2021USD ($)segment	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Revenue from External Customer [Line Items]
Return period	14 days
Gift card and site credit liabilities	$ 13,223,000	$ 9,362,000
Revenue recognition period	1 year
Loyalty point expiration period	12 months
Number of operating segments | segment	1
Number of reportable segments | segment	1
Foreign currency translation adjustments	$ (700,000)
Restricted cash, non-current	6,730,000	2,690,000
Impairments of long-lived assets	$ 0	0
Conversion period	1 year
Research and development costs	$ 28,700,000	20,700,000	$ 19,000,000
Advertising expense	54,100,000	38,400,000	39,200,000
Vopero Inc.
Revenue from External Customer [Line Items]
Investment amount	3,800,000
Investment impairment	$ 0
Minimum
Revenue from External Customer [Line Items]
Economic lives	3 years
Maximum
Revenue from External Customer [Line Items]
Economic lives	9 years
Transferred at Point in Time
Revenue from External Customer [Line Items]
Gift card and site credit liabilities	$ 1,700,000	900,000
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent
Revenue from External Customer [Line Items]
Other comprehensive losses	(400,000)	0
Loyalty Program
Revenue from External Customer [Line Items]
Revenue recognized	13,800,000
Deferred revenue recognized		6,600,000	100,000
Loyalty Program | Transferred over Time
Revenue from External Customer [Line Items]
Gift card and site credit liabilities	4,000,000	4,100,000
Gift Card
Revenue from External Customer [Line Items]
Gift card and site credit liabilities	7,300,000	6,200,000
Revenue recognized	900,000	600,000	$ 100,000
Site Credit
Revenue from External Customer [Line Items]
Gift card and site credit liabilities	$ 5,900,000	$ 3,200,000

Significant Accounting Polici_5

Significant Accounting Policies - Revenue by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Total revenue	$ 251,792	$ 186,015	$ 163,812
North America
Revenue from External Customer [Line Items]
Total revenue	240,677	186,015	163,812
Europe
Revenue from External Customer [Line Items]
Total revenue	$ 11,115	$ 0	$ 0

Significant Accounting Polici_6

Significant Accounting Policies - Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Cash and cash equivalents	$ 84,550	$ 64,485
Restricted cash, current	560	364
Restricted cash, non-current	6,730	2,690
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$ 91,840	$ 67,539	$ 87,853	$ 8,015

Significant Accounting Polici_7

Significant Accounting Policies - Schedule of Property and Equipment, Net (Details)	12 Months Ended
	Dec. 31, 2021
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Internal-use software | Minimum
Property, Plant and Equipment [Line Items]
Useful life	1 year
Internal-use software | Maximum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Computers and software | Minimum
Property, Plant and Equipment [Line Items]
Useful life	2 years
Computers and software | Maximum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Useful life	5 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Useful life	7 years

Financial Instruments and Fai_3

Financial Instruments and Fair Value Measurements - Schedule of Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets
Marketable securities	$ 121,277	$ 0
Cash equivalents:
Cash and cash equivalents	84,550	64,485
Convertible preferred stock warrant liability		800
Fair Value, Recurring
Assets
Total cash equivalents		43,460
Marketable securities	121,300
Total	174,751
Cash equivalents:
Cash and cash equivalents	53,474
Convertible preferred stock warrant liability		805
Fair Value, Recurring | U.S. treasury securities
Assets
Marketable securities	37,190
Fair Value, Recurring | Corporate debt securities
Assets
Marketable securities	55,921
Fair Value, Recurring | U.S. government agency bonds
Assets
Marketable securities	28,166
Fair Value, Recurring | Money market fund
Assets
Total cash equivalents	41,376	43,460
Fair Value, Recurring | Commercial paper
Assets
Total cash equivalents	12,098
Fair Value, Recurring | Level 1
Assets
Total cash equivalents		43,460
Total	162,653
Cash equivalents:
Convertible preferred stock warrant liability		0
Fair Value, Recurring | Level 1 | U.S. treasury securities
Assets
Marketable securities	37,190
Fair Value, Recurring | Level 1 | Corporate debt securities
Assets
Marketable securities	55,921
Fair Value, Recurring | Level 1 | U.S. government agency bonds
Assets
Marketable securities	28,166
Fair Value, Recurring | Level 1 | Money market fund
Assets
Total cash equivalents	41,376	43,460
Fair Value, Recurring | Level 1 | Commercial paper
Assets
Total cash equivalents	0
Fair Value, Recurring | Level 2
Assets
Total cash equivalents		0
Total	12,098
Cash equivalents:
Convertible preferred stock warrant liability		0
Fair Value, Recurring | Level 2 | U.S. treasury securities
Assets
Marketable securities	0
Fair Value, Recurring | Level 2 | Corporate debt securities
Assets
Marketable securities	0
Fair Value, Recurring | Level 2 | U.S. government agency bonds
Assets
Marketable securities	0
Fair Value, Recurring | Level 2 | Money market fund
Assets
Total cash equivalents	0	0
Fair Value, Recurring | Level 2 | Commercial paper
Assets
Total cash equivalents	12,098
Fair Value, Recurring | Level 3
Assets
Total cash equivalents		0
Total	0
Cash equivalents:
Convertible preferred stock warrant liability		805
Fair Value, Recurring | Level 3 | U.S. treasury securities
Assets
Marketable securities	0
Fair Value, Recurring | Level 3 | Corporate debt securities
Assets
Marketable securities	0
Fair Value, Recurring | Level 3 | U.S. government agency bonds
Assets
Marketable securities	0
Fair Value, Recurring | Level 3 | Money market fund
Assets
Total cash equivalents	0	$ 0
Fair Value, Recurring | Level 3 | Commercial paper
Assets
Total cash equivalents	$ 0

Financial Instruments and Fai_4

Financial Instruments and Fair Value Measurements - Schedule of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Liabilities
Convertible preferred stock warrant liability		$ 800
Fair Value, Recurring
Cash equivalents:
Total cash equivalents		43,460
Liabilities
Convertible preferred stock warrant liability		805
Total liabilities		805
Fair Value, Recurring | Money market fund
Cash equivalents:
Total cash equivalents	$ 41,376	43,460
Fair Value, Recurring | Level 1
Cash equivalents:
Total cash equivalents		43,460
Liabilities
Convertible preferred stock warrant liability		0
Total liabilities		0
Fair Value, Recurring | Level 1 | Money market fund
Cash equivalents:
Total cash equivalents	41,376	43,460
Fair Value, Recurring | Level 2
Cash equivalents:
Total cash equivalents		0
Liabilities
Convertible preferred stock warrant liability		0
Total liabilities		0
Fair Value, Recurring | Level 2 | Money market fund
Cash equivalents:
Total cash equivalents	0	0
Fair Value, Recurring | Level 3
Cash equivalents:
Total cash equivalents		0
Liabilities
Convertible preferred stock warrant liability		805
Total liabilities		805
Fair Value, Recurring | Level 3 | Money market fund
Cash equivalents:
Total cash equivalents	$ 0	$ 0

Financial Instruments and Fai_5

Financial Instruments and Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current	$ 121,277	$ 0
Marketable securities, between one to two years	49,000
Marketable securities, less than one year	72,200
Fair Value, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current	$ 121,300

Property and Equipment, Net (De

Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 76,028	$ 55,221
Less: accumulated depreciation and amortization	(20,562)	(14,090)
Property and equipment, net	55,466	41,131
Capitalized internal-use software	2,100	1,400
Interests costs capitalized	300	400
Interests costs	2,500	1,700
Depreciation	8,500	5,600
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	48,874	35,254
Internal-use software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,517	4,764
Computers and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,336	3,677
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,705	4,459
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	856	519
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 10,740	$ 6,548

Acquisition of Remix - Narrativ

Acquisition of Remix - Narrative (Details) - Remix Global AD - USD ($)	Oct. 07, 2021	Dec. 31, 2021	Dec. 31, 2021	Jul. 24, 2021
Business Acquisition [Line Items]
Percentage of ownership acquired				100.00%
Cash consideration	$ 25,550,000
Shares issued (in shares)	130,597
Fair value of common shares	$ 2,700,000
Acquisition revenue		$ 11,100,000
Acquisition net loss		$ 1,200,000
Transaction-related costs			$ 1,100,000
Tax deductible goodwill	$ 0

Acquisition of Remix - Estimate

Acquisition of Remix - Estimated Fair Values of the Assets Acquired and Liabilities (Details) - USD ($) $ in Thousands	Oct. 07, 2021	Dec. 31, 2021
Goodwill [Roll Forward]
Goodwill, ending balance		$ 12,238
Remix Global AD
Purchase Price
Cash consideration	$ 25,550
Delayed share issuance	2,744
Total purchase consideration	28,294
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Cash and cash equivalents	1,860
Accounts receivable	1,150
Inventory	3,657
Intangible assets	14,800	14,492
Other assets	786
Accounts payable	(3,102)
Accrued and other liabilities	(3,356)
Total net assets acquired	15,795
Goodwill [Roll Forward]
Goodwill, beginning balance		12,499
Foreign currency translation adjustments		(261)
Goodwill, ending balance	$ 12,499	$ 12,238

Acquisition of Remix - Intangib

Acquisition of Remix - Intangible Assets (Details) - Remix Global AD - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2021	Oct. 07, 2021
Business Acquisition [Line Items]
Total identified intangible assets		$ 14,800
Foreign currency translation adjustments	$ (308)
Intangible assets	$ 14,492	14,800
Customer relationships
Business Acquisition [Line Items]
Total identified intangible assets		5,200
Developed technology
Business Acquisition [Line Items]
Total identified intangible assets		4,900
Trademarks
Business Acquisition [Line Items]
Total identified intangible assets		$ 4,700

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 12,238	$ 0
Estimated future amortization expense, year one	2,700
Estimated future amortization expense, year two	2,700
Estimated future amortization expense, year three	2,400
Estimated future amortization expense, year four	1,200
Estimated future amortization expense, year five	1,200
Estimated future amortization expense, thereafter	$ 3,700

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 14,492
Accumulated amortization	(638)
Carrying amount, net	$ 13,854	$ 0
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Amortization Period (years)	8 years
Gross carrying amount	$ 5,092
Accumulated amortization	(150)
Carrying amount, net	$ 4,942
Developed technology
Finite-Lived Intangible Assets [Line Items]
Amortization Period (years)	3 years
Gross carrying amount	$ 4,798
Accumulated amortization	(373)
Carrying amount, net	$ 4,425
Trademarks
Finite-Lived Intangible Assets [Line Items]
Amortization Period (years)	9 years
Gross carrying amount	$ 4,602
Accumulated amortization	(115)
Carrying amount, net	$ 4,487

Balance Sheet Components - Inve

Balance Sheet Components - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Balance Sheet Components [Abstract]
Raw materials	$ 908	$ 0
Work in progress	670	0
Finished goods	8,247	3,519
Inventory, net	$ 9,825	$ 3,519

Balance Sheet Components - Accr

Balance Sheet Components - Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Balance Sheet Components [Abstract]
Gift card and site credit liabilities	$ 13,223	$ 9,362
Accrued compensation	6,438	3,443
Accrued vendor liabilities	6,031	3,407
Deferred revenue	5,878	5,094
Accrued taxes	5,728	4,594
Allowance for returns	6,209	3,389
Accrued other	1,746	3,252
Total	$ 45,253	$ 32,541

Lease Agreements - Narrative (D

Lease Agreements - Narrative (Details) $ in Thousands, € in Millions	12 Months Ended
	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2021EUR (€)	Dec. 31, 2021USD ($)
Lessee, Lease, Description [Line Items]
Lease not yet commenced, term of contract				10 years	10 years
Base rent of lease not yet commenced				€ 14.1	$ 15,900
Lease cost	$ 6,979	$ 6,823
Base rent			$ 4,400
Building
Lessee, Lease, Description [Line Items]
Security deposit		300			800
Letters of credit		$ 3,100			$ 6,300
Minimum
Lessee, Lease, Description [Line Items]
Lease term				20 years	20 years
Lease renewal term				12 months	12 months
Maximum
Lessee, Lease, Description [Line Items]
Lease term				146 months	146 months
Lease renewal term				120 months	120 months

Lease Agreements - Maturities o

Lease Agreements - Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
2022	$ 7,931
2023	7,808
2024	6,930
2025	6,061
2026	5,706
Thereafter	26,437
Total lease payments	60,873
Less: imputed interest	(13,843)
Less: tenant improvement allowance yet to be received	(6,102)
Total lease liabilities	40,928
Less: current lease liabilities	(3,931)	$ (3,643)
Total non-current lease liabilities	$ 36,997	$ 21,574

Lease Agreements - Lease Cost (

Lease Agreements - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating Lease Cost
Fixed Cost	$ 5,591	$ 5,568
Short-Term Lease Cost	7	58
Variable Lease Cost	1,381	1,197
Total Operating Lease Cost	$ 6,979	$ 6,823

Lease Agreements - Supplemental

Lease Agreements - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 5,401	$ 5,365

Lease Agreements - Weighted-Ave

Lease Agreements - Weighted-Average Remaining Lease Term and Discount Rate (Details)	Dec. 31, 2021	Dec. 31, 2020
Operating Leases
Weighted average remaining lease term (years)	8 years 1 month 6 days	7 years 9 months 18 days
Weighted average discount rate	5.90%	6.70%

Long-term Debt and Convertibl_3

Long-term Debt and Convertible Preferred Stock Warrants - Narrative (Details)	May 14, 2021	Feb. 28, 2021USD ($)shares	Dec. 31, 2021USD ($)shares	Mar. 26, 2021shares	Mar. 25, 2021shares	Dec. 31, 2020USD ($)amendmentshares
Debt Instrument [Line Items]
Number of amendments | amendment						3
Outstanding principal			$ 36,000,000
Convertible preferred stock warrant liability						$ 800,000
Warrants outstanding (in shares) | shares					164,973	148,994
Class B Common Stock Warrant
Debt Instrument [Line Items]
Warrants outstanding (in shares) | shares			0	164,973	164,973
Term Loan | Series E-1 Convertible Preferred Stock
Debt Instrument [Line Items]
Warrants converted (in shares) | shares		15,979
Medium-term Notes | Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 40,000,000
Borrowed amount		5,000,000
Outstanding principal		$ 40,000,000
Stated interest rate			5.50%
Floor rate	5.50%
Effective interest rate			6.65%
Medium-term Notes | Term Loan | Prime Rate | Minimum
Debt Instrument [Line Items]
Variable interest rate	1.50%

Long-term Debt and Convertibl_4

Long-term Debt and Convertible Preferred Stock Warrants - Schedule of Maturities of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
2022	$ 8,000
2023	8,000
2024	20,000
Thereafter	0
Total future principal	36,000
Less: unamortized debt discount	(673)
Less: current portion of long-term debt	(7,768)	$ (3,270)
Non-current portion of long-term debt	$ 27,559	$ 31,190

Long-term Debt and Convertibl_5

Long-term Debt and Convertible Preferred Stock Warrants - Schedule of Warrants Issued (Details) - $ / shares	Mar. 25, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Warrants outstanding (in shares)	164,973	148,994
Series D Convertible Preferred Stock, Issued 1/22/2015
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 2.2600
Warrants outstanding (in shares)	13,382	13,382
Series D Convertible Preferred Stock, Issued 4/20/2015
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 2.2600
Warrants outstanding (in shares)	13,382	13,382
Series E1 Convertible Preferred Stock, Issued 2/7/2019
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	63,917	63,917
Series F Convertible Preferred Stock, Issued 5/29/2020
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 6.8839
Warrants outstanding (in shares)	10,376	10,376
Series E1 Convertible Preferred Stock, Issued 8/14/2020
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	31,958	31,958
Series E1 Convertible Preferred Stock, Issued 11/25/2020
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	15,979	15,979
Series E1 Convertible Preferred Stock, Issued 2/28/2021
Debt Instrument [Line Items]
Exercise Price Per Share (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	15,979	0

Common Stock and Common Stock_3

Common Stock and Common Stock Warrants - Narrative (Details) $ / shares in Units, $ in Thousands	Aug. 02, 2021USD ($)$ / sharesshares	Mar. 26, 2021voteshares	Dec. 31, 2021USD ($)shares	Dec. 31, 2020USD ($)shares	Dec. 31, 2019USD ($)	Mar. 25, 2021shares
Class of Stock [Line Items]
Warrants outstanding (in shares)				148,994		164,973
Price per share of common stock (in dollars per share) | $ / shares	$ 24.25
Aggregate net proceeds | $	$ 45,500
Payments of stock issuance costs | $	$ 3,300		$ 4,729	$ 1,117	$ 0
Common Stock
Class of Stock [Line Items]
Stock converted (in shares)		65,970,938	65,971,000
Cashless exercise of common stock warrant (in shares)			128,643
Class B Common Stock Warrant
Class of Stock [Line Items]
Warrants outstanding (in shares)		164,973	0			164,973
Common stock Class A
Class of Stock [Line Items]
Number of votes for each share | vote		1
Shares sold (in shares)	2,000,000
Common stock Class A | Follow-On Public Offering | Selling Stockholders
Class of Stock [Line Items]
Shares sold (in shares)	5,388,024
Common stock Class A | Over-Allotment Option | Selling Stockholders
Class of Stock [Line Items]
Shares sold (in shares)	963,655
Common stock Class B
Class of Stock [Line Items]
Number of votes for each share | vote		10
Conversion of stock (in shares)		1
Stock converted (in shares)			164,973

Common Stock and Common Stock_4

Common Stock and Common Stock Warrants - Schedule of Common Stock Issued and Outstanding (Details) - shares	Dec. 31, 2021	Mar. 26, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Authorized (in shares)	1,120,000,000		110,000,000
Issued (in shares)	98,435,000		12,890,000
Outstanding (in shares)	98,435,000		12,890,000
Common stock Class A
Class of Stock [Line Items]
Authorized (in shares)	1,000,000,000	1,000,000,000
Issued (in shares)	57,779,000
Outstanding (in shares)	57,779,000
Common stock Class B
Class of Stock [Line Items]
Authorized (in shares)	120,000,000	120,000,000
Issued (in shares)	40,656,000
Outstanding (in shares)	40,656,000

Common Stock and Common Stock_5

Common Stock and Common Stock Warrants - Reserved for Issuance (Details) - shares	Dec. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Total (in shares)	34,427,000	89,097,000
Outstanding stock options
Class of Stock [Line Items]
Total (in shares)	19,440,000	22,775,000
Shares available for future grants
Class of Stock [Line Items]
Total (in shares)	10,668,000	202,000
Employee stock plan purchases
Class of Stock [Line Items]
Total (in shares)	2,917,000	0
Restricted stock units
Class of Stock [Line Items]
Total (in shares)	1,271,000	0
Delayed share issuance related to acquisition
Class of Stock [Line Items]
Total (in shares)	131,000	0
Convertible preferred stock
Class of Stock [Line Items]
Total (in shares)	0	65,971,000
Outstanding convertible preferred stock warrants
Class of Stock [Line Items]
Total (in shares)	0	149,000

Stock-Based Compensation Plan_2

Stock-Based Compensation Plans - Narrative (Details) - USD ($)	1 Months Ended	9 Months Ended	12 Months Ended
	Aug. 31, 2020	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in dollars per share)			$ 6.66	$ 1.72	$ 1.38
Aggregate intrinsic value of options exercised			$ 53,800,000	$ 2,900,000	$ 900,000
Compensation expense			12,959,000	7,336,000	7,678,000
Stock-based compensation costs capitalized			$ 300,000	$ 0	$ 0
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	3,588,535	924,000
Options granted (in dollars per share)	$ 2.05		$ 6,540
Fair value of stock options	$ 6,700,000
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)			0
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield			0.00%	0.00%	0.00%
Unrecognized stock-based compensation expense				$ 11,900,000
Weighted average period for unrecognized stock-based compensation expense			1 year 10 months 6 days
Outstanding stock options | 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized (in shares)		1,000,000	1,000,000	6,500,000
Expiration period			10 years
Percent of fair value			100.00%
Vesting percentage period		4 years
Compensation expense			$ 3,200,000
Outstanding stock options | 2010 Plan | Over 10% Shareholder
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of fair value			110.00%
Option Vesting Four Years From Commencement | 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage period	4 years
Vesting percentage	50.00%
Option Vesting Four Years From IPO | 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage period	4 years
Vesting percentage	50.00%
Anniversary period	1 year
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage period			4 years
Granted (in shares)			1,405,000
Conversion of stock (in shares)			1
Vesting percentage			25.00%
Weighted average period for unrecognized stock-based compensation expense			3 years 4 months 13 days
Unrecognized stock-based compensation expense			$ 21,300,000
Fair value of units vested			$ 1,700,000	$ 0
Restricted stock units | 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			1,436,451
Employee stock plan purchases
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield			0.00%
Compensation expense			$ 500,000
Weighted average period for unrecognized stock-based compensation expense			4 months 24 days
Unrecognized compensation expense			$ 300,000

Stock-Based Compensation Plan_3

Stock-Based Compensation Plans - Schedule of Stock-Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	9 Months Ended	12 Months Ended
	Aug. 31, 2020	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Options Outstanding and Available for Grant
Transferred to 2021 Plan (in shares)			(450,000)
Weighted-Average Exercise Price Per Share
Options granted (in dollars per share)			$ 6.66	$ 1.72	$ 1.38
2010 Plan
Options Outstanding and Available for Grant
Options outstanding, beginning balance (in shares)			19,440,000		22,775,000
Options granted (in shares)	3,588,535	924,000
Options exercised (in shares)		(3,480,000)
Options forfeited (in shares)		172,000
Options expired (in shares)		(779,000)
Options outstanding, ending balance (in shares)			19,440,000		22,775,000
Options outstanding and exercisable (in shares)			11,434,000
Weighted-Average Exercise Price Per Share
Beginning balance (in dollars per share)			$ 2,060	1.81
Options granted (in dollars per share)	$ 2.05		6,540
Options exercised (in dollars per share)			1,510
Options forfeited and expired (in dollars per share)			2,570
Ending balance (in dollars per share)			2,060	$ 1.81
Options outstanding and exercisable (in dollars per share)			$ 1,810
Weighted-Average Remaining Contractual Life (years)
Options outstanding (years)			6 years 3 months 14 days	7 years 4 months 9 days
Options outstanding and exercisable (in shares)			5 years 3 months 7 days
Aggregate Intrinsic Value (in thousands)
Options outstanding			$ 208,042	$ 107,696
Options outstanding and exercisable			$ 125,242
Outstanding stock options | 2010 Plan
Options Outstanding and Available for Grant
Options available for grant, beginning balance (in shares)				202,000
Options authorized (in shares)		1,000,000	1,000,000	6,500,000
Options available for grant, ending balance (in shares)			0		202,000

Stock-Based Compensation Plan_4

Stock-Based Compensation Plans - Schedule of Fair Value Assumptions (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, minimum	59.40%	46.90%	45.50%
Expected volatility, maximum	61.80%	54.90%	47.80%
Average risk-free rate, minimum	0.44%	0.28%	1.52%
Average risk-free rate, maximum	1.10%	1.55%	2.44%
Dividend yield	0.00%	0.00%	0.00%
Outstanding stock options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years	5 years	5 years 6 months 18 days
Outstanding stock options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	10 years	10 years	6 years 3 months
Employee stock plan purchases
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, minimum	60.65%
Expected volatility, maximum	71.25%
Average risk-free rate, minimum	0.05%
Average risk-free rate, maximum	0.10%
Dividend yield	0.00%
Weighted average fair value of purchase rights (in dollars per share)	$ 5.28
Employee stock plan purchases | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 months
Employee stock plan purchases | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	8 months 4 days

Stock-Based Compensation Plan_5

Stock-Based Compensation Plans - Schedule of RSU Activity (Details) - Restricted stock units $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)$ / sharesshares
Shares (in thousands)
Outstanding at beginning of period (in shares) | shares	0
Granted (in shares) | shares	1,405,000
Vested (in shares) | shares	(84,000)
Forfeited and cancelled (in shares) | shares	(81,000)
Outstanding at end of period (in shares) | shares	1,240,000
Weighted-Average Grant-Date Fair Value
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 0
Granted (in dollars per share) | $ / shares	18.92
Vested (in dollars per share) | $ / shares	20.21
Forfeited (in dollars per share) | $ / shares	19.83
Outstanding at end of period (in dollars per share) | $ / shares
Weighted-Average Remaining Contractual Life (years)	1 year 9 months 7 days
Aggregate Intrinsic Value (in thousands) | $	$ 15,813

Stock-Based Compensation Plan_6

Stock-Based Compensation Plans - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 12,959	$ 7,336	$ 7,678
Operations, product and technology
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	4,241	3,739	3,877
Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,405	1,067	1,018
Sales, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 7,313	$ 2,530	$ 2,783

Commitment and Contingencies (D

Commitment and Contingencies (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
2022	$ 11,902
2023	3,134
2024	1,026
2025	939
2026	0
Thereafter	0
Total future minimum payments	$ 17,001

Retirement Plan (Details)

Retirement Plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Employer contributions	$ 0	$ 0	$ 0

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Contingency [Line Items]
Loss before provision for income taxes	$ (63,096,000)	$ (47,821,000)	$ (38,161,000)
Provision for income taxes	80,000	56,000	$ 36,000
Net operating loss carryforwards	75,804,000	53,550,000
Valuation allowance, increase	18,800,000	10,500,000
Unrecognized tax benefits	0
Accrued interest and penalties	0	$ 0
Domestic Tax Authority
Income Tax Contingency [Line Items]
Loss before provision for income taxes	(61,900,000)
Operating loss carryforwards	297,700,000
Net operating loss carryforwards	189,400,000
Foreign Tax Authority
Income Tax Contingency [Line Items]
Loss before provision for income taxes	(1,200,000)
Operating loss carryforwards	12,000,000
State and Local Jurisdiction
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 203,200,000

Income Taxes - Income Tax Recon

Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Tax at federal statutory rate	$ (13,250)	$ (10,042)
State taxes, net of federal effect	63	42
Non-deductible expenses	156	67
Foreign tax rate differential	259	0
Stock based compensation	(3,086)	1,077
Change in valuation allowance	15,712	8,814
Other	226	98
Provision for income taxes	$ 80	$ 56	$ 36

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Accruals and reserves	$ 2,043	$ 2,472
Inventory and deferred revenue	770	690
Stock compensation	2,128	1,151
Other	1,417	670
Net operating loss carryforwards	75,804	53,550
Gross deferred tax assets	82,162	58,533
Less: valuation allowance	(75,348)	(56,581)
Total deferred tax assets	6,814	1,952
Deferred tax liabilities:
Fixed assets	(4,876)	(1,952)
Intangibles	(1,938)	0
Gross deferred tax liabilities	(6,814)	(1,952)
Net deferred tax assets	$ 0	$ 0

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Stockholders (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	20,858,000	88,895,000	84,084,000
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	19,440,000	22,775,000	17,985,000
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	1,271,000	0	0
Delayed share issuance related to acquisition
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	130,000	0	0
Employee stock purchase plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	17,000	0	0
Convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	0	65,971,000	65,928,000
Outstanding convertible preferred stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	0	149,000	171,000