BioLargo (BLGO) 10-K 31 Mar 23 2022 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2022	Mar. 29, 2023	Jun. 30, 2022
Document Information [Line Items]
Entity Central Index Key	0000880242
Entity Registrant Name	BIOLARGO, INC.
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2022
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Document Transition Report	false
Entity File Number	000-19709
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	65-0159115
Entity Address, Address Line One	14921 Chestnut St.
Entity Address, City or Town	Westminster
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92683
City Area Code	888
Local Phone Number	400-2863
Title of 12(b) Security	Common Stock
Trading Symbol	BLGO
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	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 40,752,460
Entity Common Stock, Shares Outstanding		283,192,091
Auditor Name	HASKELL & WHITE LLP
Auditor Firm ID	200
Auditor Location	Irvine, California

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 1,851,000	$ 962,000
Accounts receivable, net of allowance	1,064,000	513,000
Inventories, net of allowance	120,000	241,000
Prepaid expenses and other current assets	118,000	85,000
Total current assets	3,153,000	1,801,000
Equipment, net of depreciation	287,000	61,000
Other non-current assets	124,000	69,000
Investment in South Korean joint venture	33,000	48,000
Right of use, operating lease, net of amortization	867,000	453,000
Clyra Medical prepaid marketing (Note 10)	394,000	591,000
Total assets	4,858,000	3,023,000
Current liabilities:
Accounts payable and accrued expenses	940,000	559,000
Debt obligations, net of discount (Note 4)	100,000	314,000
Deferred revenue	17,000	89,000
Lease liability	97,000	103,000
Deposits	184,000	79,000
Total current liabilities	1,576,000	1,374,000
Long-term liabilities:
Debt obligations, net of current (Note 4)	237,000	180,000
Lease liability, net of current	773,000	349,000
Total long-term liabilities	1,271,000	716,000
Total liabilities	2,847,000	2,090,000
COMMITMENTS AND CONTINGENCIES (Note 13)
STOCKHOLDERS’ EQUITY (DEFICIT):
Preferred Series A, $0.00067 Par Value, 50,000,000 Shares Authorized, -0- Shares Issued and Outstanding, at December 31, 2022 and December 31, 2021	0	0
Common stock, $0.00067 Par Value, 400,000,000 Shares Authorized, 278,462,706 and 255,893,726 Shares Issued, at December 31, 2022 and December 31, 2021	186,000	171,000
Additional paid-in capital	148,435,000	143,718,000
Accumulated deficit	(143,594,000)	(139,121,000)
Accumulated other comprehensive loss	(149,000)	(115,000)
Total BioLargo Inc. and subsidiaries stockholders’ equity	4,878,000	4,653,000
Non-controlling interest (Note 10)	(2,867,000)	(3,720,000)
Total stockholders’ equity	2,011,000	933,000
Total liabilities and stockholders’ equity	4,858,000	3,023,000
Entities, Excluding Partially Owned Subsidiary [Member]
Current liabilities:
Accounts payable and accrued expenses	940,000	559,000
Partially Owned Subsidiary [Member]
Current liabilities:
Accounts payable and accrued expenses	238,000	230,000
Long-term liabilities:
Debt obligations, net of current (Note 4)	$ 261,000	$ 187,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
Convertible Preferred Stock, Par Value (in dollars per share)	$ 0.00067	$ 0.00067
Convertible Preferred Stock, Shares Authorized (in shares)	50,000,000	50,000,000
Convertible Preferred Stock, Shares Issued (in shares)	0	0
Convertible Preferred Stock, Shares Outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.00067	$ 0.00067
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	278,462,706	255,893,726

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenue from Contract with Customer, Including Assessed Tax	$ 5,884,000	$ 2,531,000
Cost of revenue
Cost of Goods and Services Sold	(3,027,000)	(1,428,000)
Gross profit	2,857,000	1,103,000
Operating expenses:
Selling, general and administrative expenses	6,731,000	6,172,000
Research and development	1,319,000	1,367,000
Asset Impairment Charges, Total	197,000	342,000
Total operating expenses	8,247,000	7,881,000
Operating loss	(5,390,000)	(6,778,000)
Other income (expense):
PPP forgiveness	174,000	43,000
Grant income	74,000	55,000
Tax credit income	63,000	20,000
Interest expense	(53,000)	(234,000)
Total other (expense) income	258,000	(116,000)
Net loss	(5,132,000)	(6,894,000)
Net (loss) income attributable to noncontrolling interest	(659,000)	186,000
Net loss attributable to common stockholders	$ (4,473,000)	$ (7,080,000)
Net loss per share attributable to common stockholders:
Loss per share attributable to stockholders – basic and diluted (in dollars per share)	$ (0.02)	$ (0.03)
Weighted average number of common shares outstanding: (in shares)	268,302,234	247,203,625
Comprehensive loss attributable to common stockholders
Net loss	$ (5,132,000)	$ (6,894,000)
Foreign currency translation	(34,000)	(14,000)
Comprehensive loss	(5,166,000)	(6,908,000)
Comprehensive income (loss) attributable to noncontrolling interest	(659,000)	186,000
Comprehensive loss attributable to stockholders	(4,507,000)	(7,094,000)
Product [Member]
Revenue from Contract with Customer, Including Assessed Tax	4,434,000	1,572,000
Cost of revenue
Cost of Goods and Services Sold	(2,177,000)	(781,000)
Service [Member]
Revenue from Contract with Customer, Including Assessed Tax	1,450,000	959,000
Cost of revenue
Cost of Goods and Services Sold	$ (850,000)	$ (647,000)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity (Deficit) - USD ($)	Preferred Stock [Member] Noncontrolling Interest [Member]	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interest [Member]	Total
Balance (in shares) at Dec. 31, 2020			225,885,682
Balance at Dec. 31, 2020			$ 151,000	$ 135,849,000	$ (132,041,000)	$ (101,000)	$ (4,093,000)	$ (235,000)
Conversion of notes (in shares)			1,966,439
Conversion of notes			$ 1,000	327,000	0	0	0	328,000
Issuance of common stock for services (in shares)			2,127,467
Issuance of common stock for services			$ 1,000	366,000	0	0	0	367,000
Issuance of common stock for interest (in shares)			81,777
Issuance of common stock for interest			$ 0	16,000	0	0	0	16,000
Sale of stock for cash (in shares)			29,691,886
Sale of stock for cash			$ 20,000	4,862,000	0	0	0	$ 4,882,000
Warrant exercise (in shares)			1,283,333					1,283,333
Warrant exercise			$ 1,000	163,000	0	0	0	$ 164,000
Return of shares held by Clyra Medical (re Scion) (in shares)			(5,142,858)
Return of shares held by Clyra Medical (re Scion)			$ (3,000)	(921,000)	0	0	1,286,000	362,000
Stock option compensation expense			0	1,308,000	0	0	0	1,308,000
Fair value of warrant recorded as debt discount			0	35,000	0	0	0	35,000
Noncontrolling interest allocation			0	1,149,000	0	0	(1,149,000)	0
Clyra stock options issued for services			0	564,000	0	0	0	564,000
Issuance of Clyra common stock for cash			0	0	0	0	50,000	50,000
Net loss			0	0	(7,080,000)	0	186,000	(6,894,000)
Foreign currency translation			0	0	0	(14,000)	0	(14,000)
Foreign currency translation			$ 0	0	0	(14,000)	0	(14,000)
Balance (in shares) at Dec. 31, 2021			255,893,726
Balance at Dec. 31, 2021			$ 171,000	143,718,000	(139,121,000)	(115,000)	(3,720,000)	933,000
Issuance of common stock for services (in shares)			1,448,512
Issuance of common stock for services			$ 1,000	290,000	0	0	0	291,000
Sale of stock for cash (in shares)			19,580,225
Sale of stock for cash			$ 13,000	3,604,000	0	0	0	3,617,000
Stock option compensation expense			0	1,663,000	0	0	0	1,663,000
Noncontrolling interest allocation			0	(1,287,000)	0	0	1,287,000	0
Clyra stock options issued for services			0	408,000	0	0	0	408,000
Issuance of Clyra common stock for cash	$ 225,000	$ 225,000	0	0	0	0
Net loss			0	0	(4,473,000)	0	(659,000)	(5,132,000)
Foreign currency translation			$ 0	0	0	(34,000)	0	(34,000)
Stock issued as commitment fee (in shares)			1,250,000
Stock issued as commitment fee			$ 1,000	(1,000)	0	0	0	0
Stock option exercise (in shares)			290,243
Stock option exercise			$ 0	40,000	0	0	0	40,000
Foreign currency translation			$ 0	0	0	(34,000)	0	(34,000)
Balance (in shares) at Dec. 31, 2022			278,462,706
Balance at Dec. 31, 2022			$ 186,000	$ 148,435,000	$ (143,594,000)	$ (149,000)	$ (2,867,000)	$ 2,011,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities
Net loss	$ (5,132,000)	$ (6,894,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock option compensation expense	2,071,000	1,872,000
Common stock issued for services	291,000	367,000
Impairment, Long-Lived Asset, Held-for-Use, Total	197,000	342,000
Inventory reserve	158,000	0
Common stock issued for interest	0	16,000
Interest expense related to amortization of the discount on convertible notes payable	17,000	119,000
Loss on investment in South Korean joint venture	15,000	15,000
PPP forgiveness	(174,000)	(43,000)
Amortization and depreciation expense	45,000	20,000
Changes in assets and liabilities:
Accounts receivable	(551,000)	(29,000)
Inventories	(35,000)	36,000
Deferred revenue	(72,000)	41,000
Prepaid expenses and other assets	(90,000)	(57,000)
Right of use and lease liability, net	3,000	0
Deposit	105,000	79,000
Net cash used in operating activities	(2,762,000)	(3,937,000)
Cash flows from investing activities
Equipment purchases	(271,000)	(21,000)
Patent purchase	0	(13,000)
Net cash used in investing activities	(271,000)	(34,000)
Cash flows from financing activities
Proceeds from sale of common stock	3,617,000	4,882,000
Proceeds from warrant exercise	0	164,000
Proceeds from BioLargo stock option exercise	40,000	0
Repayment of note payable and line of credit	0	(828,000)
Repayment by Clyra on inventory line of credit	(26,000)	(37,000)
Proceeds from sale of preferred stock in Clyra Medical	225,000	0
Proceeds from Clyra Medical note payable	100,000	0
Net cash provided by financing activities	3,956,000	4,231,000
Net effect of foreign currency translation	(34,000)	(14,000)
Net change in cash	889,000	246,000
Cash at beginning of year	962,000	716,000
Cash at end of year	1,851,000	962,000
Supplemental disclosures of cash flow information
Interest	36,000	99,000
Income taxes	3,000	2,000
Short-term lease payments not included in lease liability	99,000	52,000
Non-cash investing and financing activities
Return of in-process research and development (Scion)	0	1,804,000
Cancellation of Clyra debt obligations and accounts payable (Scion)	0	(1,465,000)
Liability to Scion shareholders	0	(540,000)
Fair value of warrants issued with convertible notes and letter of credit	0	35,000
Conversion of convertible notes payable into common stock	0	328,000
Fair value of common stock issued to Lincoln Park as finance fee	240,000	0
Present value of new operating right of use and lease liability	443,000	186,000
Allocation of stock option expense within noncontrolling interest	1,287,000	1,149,000
Clyra Medical Common Stock [Member]
Cash flows from financing activities
Proceeds from sale of common stock	0	50,000
Entities, Excluding Partially Owned Subsidiary [Member]
Changes in assets and liabilities:
Accounts payable and accrued expenses	382,000	47,000
Accounts payable and accrued expenses	382,000	47,000
Partially Owned Subsidiary [Member]
Changes in assets and liabilities:
Accounts payable and accrued expenses	8,000	132,000
Accounts payable and accrued expenses	$ 8,000	$ 132,000

Note 1 - Business and Organizat

Note 1 - Business and Organization	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	1. Description of Business BioLargo, Inc. (“BioLargo”, or the “Company”) invents, develops, and commercializes innovative platform technologies to solve challenging environmental problems like PFAS contamination (per- and polyfluoroalkyl substances), advanced water and wastewater treatment, industrial odor control, air quality control, infection control, and myriad environmental remediation challenges. Our business strategy is straightforward: we invent or acquire technologies that we believe have the potential to be disruptive in large commercial markets; we develop and validate these technologies to advance and promote their commercial success as we leverage our considerable scientific, engineering, and entrepreneurial talent; we then monetize these technical assets through a variety of business structures that may Liquidity / Going concern The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and the settlement of liabilities and commitments in the normal course of our business. For the year ended December 31, 2022, December 31, 2022, not 2023 During the year ended December 31, 2022, 12. not December 31, 2022, 3 3 6 As of December 31, 2022, March 2023 14 2024 10 Subsequent to December 31, 2022, 14 If we are unable to rely on our current arrangement with Lincoln Park to fund our working capital requirements, we will have to rely on other forms of financing, and there is no The foregoing factors raise substantial doubt about our ability to continue as a going concern, unless we are able to continue to raise funds through stock sales to Lincoln Park or other private financings, and in the long term, our ability to attain a reasonable threshold of operating efficiencies and achieve profitable operations by licensing or otherwise commercializing products incorporating our technologies. The consolidated financial statements do not Organization We are a Delaware corporation formed in 1991. six 2006; 2009; 2019, 2022; 2014; 2016. 11 2017, 2012. 2, 10

Note 2 - Summary of Significant

Note 2 - Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Significant Accounting Policies [Text Block]	Note 2. Principles of Consolidation The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, and partially-owned subsidiaries BLEST and Clyra Medical. All intercompany accounts and transactions have been eliminated. Foreign Currency The Company has designated the functional currency of BioLargo Water, Inc., our Canadian subsidiary, to be the Canadian dollar. Therefore, translation gains and losses resulting from differences in exchange rates are recorded in accumulated other comprehensive income. Cash and Cash Equivalents The Company considers all highly liquid investments with maturities of three one $250,000 not As of December 31, 2022 2021, December 31, 2022 December 31, 2021 BioLargo, Inc. and subsidiaries $ 1,685 $ 941 Clyra Medical Technologies, Inc. 166 21 Total $ 1,851 $ 962 Accounts Receivable Trade accounts receivable are recorded net of allowances for doubtful accounts. Estimates for allowances for doubtful accounts are determined based on payment history and individual customer circumstances. The allowance for doubtful accounts as of December 31, 2022 2021 $ 12,000 Credit Concentration We have a limited number of customers that account for significant portions of our revenue. During the year ended December 31, 2022, two December 31, 2021, three December 31, 2022 December 31, 2021 Customer A 47 % <10 % Customer B 10 % <10 % Customer C <10 % 14 % Customer D <10 % 11 % Customer E <10 % 11 % We had one 10% December 31, 2022 two December 31, 2021, December 31, 2022 December 31, 2021 Customer A 24 % <10 % Customer F <10 % 32 % Customer G <10 % 12 % Inventory Inventories are stated at the lower of cost or net realizable value using the average cost method. The allowance for obsolete inventory as of December 31, 2022 2021 $3,000. December 31, 2022 December 31, 2021 Raw material $ 46 $ 108 Finished goods 74 133 Total $ 120 $ 241 Other Non-Current Assets Other non-current assets consisted of (i) security deposits related to our business offices, (ii) three October 22, 2021, December 31, 2022 December 31, 2021 Patents $ 34 $ 34 Security deposits 36 35 Tax credit receivable 54 — Total $ 124 $ 69 Equity Method of Accounting On March 20, 2020, We account for our investment in the joint venture under the equity method of accounting. We have determined that while we have significant influence over the joint venture through our technology license and our position on the Board of Directors, we do not December 31, 2022 2021, Impairment Long-lived and definite lived intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not For the year ended December 31, 2022, 9 For the year ended December 31, 2021, 9 9 December 31, 2022 2021 $342,000, Earnings (Loss) Per Share We report basic and diluted earnings (loss) per share (“EPS”) for common and common share equivalents. Basic EPS is computed by dividing reported earnings by the weighted average shares outstanding. Diluted EPS is computed by adding to the weighted average shares the dilutive effect if convertible notes payable, stock options and warrants were exercised into common stock. For the years ended December 31, 2022 2021, Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and revenues and expenses during the period reported. Actual results could differ from those estimates. Estimates are used when accounting for stock-based transactions, debt transactions, derivative liabilities, allowance for bad debt, asset depreciation and amortization, impairment expense, among others. The methods, estimates and judgments we use in applying these most critical accounting policies have a significant impact on the results of our financial statements. Share-Based Compensation Expense We recognize compensation expense for stock option awards on a straight-line basis over the applicable service period of the award, which is the vesting period. Fair value is determined on the grant date. Share-based compensation expense is based on the grant date fair value estimated using the Black-Scholes Option Pricing Model. For stock and stock options issued to consultants and other non-employees for services, the Company measures and records an expense as of the earlier of the date at which either: a commitment for performance by the non-employee has been reached or the non-employee’s performance is complete. The equity instruments are measured at the current fair value, and for stock options, the instruments are measured at fair value using the Black Scholes option model. The following methodology and assumptions were used to calculate share-based compensation for the years ended December 31, 2022 2021: 2022 2021 Non Plan 2018 Plan Non Plan 2018 Plan Risk free interest rate 2.32 – 3.83 % 2.32 – 3.83 % 1.49 – 1.73 % 0.93 – 1.73 % Expected volatility 114 – 117 % 114 – 117 % 118 – 124 % 118 – 124 % Expected dividend yield — — — — Forfeiture rate — — — — Life in years 10 10 10 10 Expected price volatility is the measure by which our stock price is expected to fluctuate during the expected term of an option. Expected volatility is derived from the historical daily change in the market price of our common stock, as we believe that historical volatility is the best indicator of future volatility. The risk-free interest rate used in the Black-Scholes calculation is based on the prevailing U.S. Treasury yield as determined by the U.S. Federal Reserve. We have never paid any cash dividends on our common stock and do not Warrants Warrants issued with our convertible and non-convertible debt instruments are accounted for under the fair value and relative fair value method. The warrant is first not. not If the warrant is determined to not Convertible debt instruments are recorded at fair value, limited to a relative fair value based upon the percentage of its fair value to the total fair value including the fair value of the warrant. The warrant relative fair values are also recorded as a discount to the convertible promissory notes. As present, these equity features of the convertible promissory notes have recorded a discount to the convertible notes that is substantially equal to the proceeds received. Non-Cash Transactions We have established a policy relative to the methodology to determine the value assigned to each intangible we acquire, and/or services or products received for non-cash consideration of our common stock. The value is based on the market price of our common stock issued as consideration, at the date of the agreement of each transaction or when the service is rendered or product is received. Revenue Recognition We account for revenue in accordance with ASC 606, Step 1: Identify the contract(s) with a customer. Step 2: Identify the performance obligations in the contract. Step 3: Determine the transaction price. Step 4: Allocate the transaction price to the performance obligations in the contract. Step 5: Recognize revenue when (or as) the entity satisfies a performance obligation. The Company’s products are sold through a contract with the customer and a written purchase order, in which the details of the contract are defined including the transaction price and method of shipment. The only performance obligation is to create and ship the product, and each product has separate pricing. Revenue is recognized at a point in time when the goods are shipped if the agreement is FOB manufacturer, and when goods are delivered if FOB destination. Revenue is recognized with a reduction for sales discounts, as appropriate and negotiated in the customer’s purchase order. Service contracts are performed through a written contract, which specifies the performance obligations and the rate at which the services will be billed, typically by time and materials. Each service is separately negotiated and priced. Revenue is recognized as services are performed and completed, or, for services related to product installations, at the completion of the installation. A few contracts have called for milestone or fixed cost payments, where we invoice an agreed-to amount per month for the life of the contract. In these instances, completed work, billed hourly, is recognized as revenue. If the billing amount is greater or lesser than the completed work, a receivable or payable is created. These accounts are adjusted upon additional billings as the work is completed. To date, there have been no In the event that we generate revenues from royalties or license fees from our intellectual property, we anticipate a licensee would pay a license fee in one Clyra also has certain distribution agreements that call for consigned inventory. Although the product is shipped to a third not Government Grants We have been awarded multiple research grants from the private and public Canadian research programs. Income we receive directly from grants is recorded as other income. We have been awarded over 80 first 2015. third third six eighteen not The grants typically provide for (i) recurring monthly amounts, (ii) reimbursement of costs for research talent for which we invoice to request payment, and (iii) ancillary cost reimbursement for research talent travel related costs. All awarded grants have specific requirements on how the money is spent, typically to employ researchers. None may Not no Income Taxes The asset and liability approach is used to recognize deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of asset and liabilities. Deferred tax assets and liabilities are determined based on the differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The effect on deferred tax asset and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. We account for uncertainties in income tax law under a comprehensive model for the financial statement recognition, measurement, presentation and disclosure of uncertain tax positions taken or expected to be taken in income tax returns as prescribed by generally accepted accounting principles (“GAAP”). Under GAAP, the tax effects of a position are recognized only if it is “more-likely-than- not” not not” no December 31, 2022 2021. The Company assessed its earnings history, trends and estimates of future earnings and determined that the deferred tax asset could not December 31, 2022. The Company recognizes interest and penalties on income taxes as a component of income tax expense, should such an expense be realized. Fair Value of Financial Instruments Management believes the carrying amounts of the Company’s financial instruments as of December 31, 2022 2021 Tax Credits Our research and development activities in Canada may not Leases In February 2016, No. 2016 02, 11 January 1, 2019 July 2018, may 842, December 31, 2022, $867,000 Equipment Equipment is stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, which range from 3 - 5 Recent Accounting Pronouncements None.

Note 3 - Sale of Stock for Cash

Note 3 - Sale of Stock for Cash	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Stock Purchase Agreement [Text Block]	Note 3. Lincoln Park Financing On December 13, 2022, “2022 three may three 12 no first 2022 1 December 23, 2022. January 19, 2023. Pursuant to the 2022 Pursuant to a similar purchase agreement dated March 30, 2020, December 31, 2022 2021, December 31, 2022, 2022 14 Unit Offerings During the year ended December 31, 2022, six five 6, December 31, 2021, six five 6,

Note 4 - Debt Obligations

Note 4 - Debt Obligations	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Debt Disclosure [Text Block]	Note 4. The following table summarizes our debt obligations outstanding as of December 31, 2022 2021 not 10, December 31, 2022 2021 Current portion of debt: SBA Paycheck Protection Program loan $ 43 $ 314 Convertible note payable, matures March 1, 2023 50 — SBA EIDL Loan, matures July 2053, current portion 10 — Debt discount, net of amortization (3 ) — Total current portion of debt $ 100 $ 314 Long-term debt: SBA Paycheck Protection Program loans, matures May 2025 $ 97 $ — Convertible note payable, matures March 1, 2023 — 50 Debt discount, net of amortization — (20 ) SBA EIDL Loan, matures July 2053 140 150 Total long-term debt, net of current $ 237 $ 180 Total $ 337 $ 494 For the years ended December 31, 2022 2021, Cash payment of Debt Obligations On August 13, 2021, one August 12, 2021. On March 1, 2021, August 9, 2019, August 9, 2021. On March 1, 2021, September 1, 2019. no Conversion of Debt Obligations On its maturity date of April 20, 2021, Convertible note payable, matures March 1, 2023 On March 8, 2018, sixty March 1, 2021, March 1, 2023, 6 December 31, 2022, 14 SBA Program Loans On February 7, 2022, $174,000 May 12, 2022, May 2025. March 19, 2021, In July 2020, January 2023.

Note 5 - Share-based Compensati

Note 5 - Share-based Compensation	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	Note 5. Issuance of Common Stock in exchange for Services Payment of Officer Salaries During the year ended December 31, 2022, September 30, 2022, 268,330shares $0.27; June 30, 2022, During the year ended December 31, 2021, December 31, 2021, September 30, 2021, $0.19; March 31, 2021, Shares issued to Officers are unvested at the date of grant and subject to a lock-up agreement restricting vesting and sale until the earlier of (i) the consummation of a sale (in a single transaction or in a series of related transactions) of BioLargo by means of a sale of (a) a majority of the then outstanding common stock of BioLargo (whether by merger, consolidation, sale or transfer of common stock, reorganization, recapitalization or otherwise) or (b) all or substantially all of the assets of BioLargo; and (ii) the successful commercialization of BioLargo’s products or technologies as demonstrated by its receipt of at least $3,000,000 in cash, or the recognition of $3,000,000 in revenue, over a 12 Payment of Consultant Fees During 2022, December 30, 2022, September 30, 2022, 110,498 $0.27; June 30, 2022, $0.18; March 31, 2022, During 2021, December 31, 2021, September 30, 2021, June 30, 2020, March 31, 2021, All of these offerings and sales were made in reliance on the exemption from registration contained in Section 4 2 not Payment of Interest During June 2021, All of these offerings and sales were made in reliance on the exemption from registration contained in Section 4 2 not Stock Option Expense During the years ended December 31, 2022 2021, 2018 10 2018 On June 22, 2018, 2018 “2018 may June 22, 2028. 2018 2018 January 1 st December 31, 2022, Activity for our stock options under the 2018 December 31, 2022, December 31, 2021, Weighted Average Aggregate Options Exercise Price per Intrinsic Outstanding Price per share share Value (1) Balance, December 31, 2020 18,865,525 $0.12 – 0.43 $ 0.19 Granted 4,320,617 $0.13 – 0.23 $ 0.19 Balance, December 31, 2021 23,186,142 $0.12 – 0.43 $ 0.19 Granted 6,322,233 $0.18 – 0.27 $ 0.22 Exercised (290,243 ) $0.13 – 0.23 $ 0.16 Expired (733,583 ) $0.12 – 0.40 $ 0.33 Balance, December 31, 2022 28,484,549 $0.12 – 0.43 $ 0.19 Non-vested (3,746,708 ) $0.18 – 0.27 $ 0.19 Vested, December 31, 2022 24,737,841 $0.12 – 0.43 $ 0.19 $ 596,000 ( 1 December 31, 2022. The options granted to purchase 6,322,233 shares during the year ended December 31, 2022 $97,000; $401,000; four Chief Financial Officer Contract Extension On March 22, 2022, February 1, 2008 ( March 22, 2022 ( one January 31, 2023 ( 14 As the sole compensation for the Extended Term, Mr. Dargan was issued an option (“Option”) to purchase 25,000 shares of the Company’s common stock for each month during the Extended Term (thus, an option to purchase 300,000 shares reflecting an extended term of 12 March 22, 2022, March 22, 2022, March 22, 2022, ten 2018 The Option is Mr. Dargan’s sole compensation for the Extended Term. As was the case in all prior terms of his engagement, there is no no not 14, 2007 On September 7, 2007, April 29, 2011, 2007 “2007 may September 7, 2017. September 2017, Activity for our stock options under the 2007 December 31, 2022 2021 Weighted Average Aggregate Options Exercise Price per intrinsic Outstanding price per share share Value (1) Balance, December 31, 2020 5,689,363 $ 0.23 – 0.94 $ 0.44 Expired (2,810,117 ) 0.34 – 0.51 0.38 Balance, December 31, 2021 2,879,246 $ 0.23 – 0.94 $ 0.49 Expired (975,161 ) 0.35 – 0.40 0.36 Balance, December 31, 2022 1,904,085 $ 0.23 – 0.94 $ 0.56 $ — ( 1 December 31, 2022. Non-Plan Options issued Activity of our non-plan stock options issued for the years ended December 31, 2022 2021 Weighted Non-plan average Aggregate Options Exercise price per intrinsic outstanding price per share share value (1) Balance, December 31, 2020 20,749,583 $ 0.12 – 1.00 $ 0.41 Granted 169,624 0.17 – 0.23 0.20 Expired (800,000 ) 1.00 1.00 Balance, December 31, 2021 20,119,207 $ 0.12 – 0.83 $ 0.39 Granted 571,358 0.17 – 0.27 0.19 Expired (1,666,736 ) 0.30 – 0.40 0.31 Balance, December 31, 2022 19,023,829 $ 0.12 – 0.83 $ 0.39 Unvested (507,500 ) 0.45 0.45 Vested and outstanding, December 31, 2022 18,516,329 $ 0.12 – 0.83 $ 0.39 $ 77,000 ( 1 December 31, 2022. During the year ended December 31, 2022, $0.27 During the year ended December 31, 2021,

Note 6 - Warrants

Note 6 - Warrants	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Warrants [Text Block]	Note 6. We have certain warrants outstanding to purchase our common stock, at various prices, as described in the following table: Weighted average Aggregate Warrants Exercise price per intrinsic outstanding price per share share value (1) Balance, December 31, 2020 32,980,989 $ 0.13 – 1.00 $ 0.29 Granted 11,096,992 0.12 – 0.14 0.21 Exercised (1,283,333 ) 0.12 – 0.14 0.13 Expired (6,029,086 ) 0.12 – 0.70 0.30 Balance, December 31, 2021 36,765,562 $ 0.13 – 1.00 $ 0.27 Granted 27,137,048 0.12 – 0.14 0.23 Exercised — Expired (14,879,152 ) 0.12 – 0.48 0.24 Balance, December 31, 2022 49,023,398 $ 0.13 – 1.00 $ 0.26 $ 691,000 ( 1 December 31, 2022. Warrants issued in Unit Offerings During the year ended December 31, 2022, 3 six five During the year ended December 31, 2021, 3 six five Warrant issued in conjunction with amendment to note payable On March 1, 2021, 4 five two Exercise of Warrants During the year ended December 31, 2021, Fair Value – Interest Expense To determine interest expense related to our outstanding warrants issued in conjunction with debt offerings, the fair value of each award grant is estimated on the date of grant using the Black-Scholes option pricing model and the relative fair values are amortized over the life of the warrant. For the determination of expense of warrants issued for services, extinguishment of debt and settlement management also uses the option-pricing model. The principal assumptions we used in applying this model were as follows: 2022 2021 Risk free interest rate 3.69 – 3.88% 0.71% Expected volatility 40% 100% Expected dividend yield — — Forfeiture rate — — Expected life in years 3 .5 – 5 The risk-free interest rate is based on U.S. Treasury yields in effect at the time of grant. Expected volatilities are based on historical volatility of our common stock. The expected life in years is based on the contract term of the warrant.

Note 7 - Accounts Payable and A

Note 7 - Accounts Payable and Accrued Expenses	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Accounts Payable and Accrued Liabilities Disclosure [Text Block]	Note 7. As of December 31, 2022, Category BioLargo ONM BLEST Water Intercompany amounts Totals Accounts payable $ 187 $ 486 $ 7 $ 119 $ (82 ) $ 717 Accrued payroll 20 58 120 — — 198 Accrued interest 25 — — — — 25 Total $ 940 As of December 31, 2021, Category BioLargo ONM BLEST Water Intercompany amounts Totals Accounts payable $ 156 $ 72 $ 73 $ 96 $ (47 ) $ 350 Accrued payroll 37 53 94 — — 184 Accrued interest 25 — — — — 25 Total $ 559 See Note 10,

Note 8 - Provision for Income T

Note 8 - Provision for Income Taxes	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Income Tax Disclosure [Text Block]	Note 8. Given our historical losses from operations, income tax obligations have been limited to the minimum franchise tax assessed by the State of California. Since 2016, not 80%. not not not At December 31, 2022, $101,000,000 $54,000,000 may not December 22, 2018, post‑2018 may pre‑2018 20 1 2 80% 172 no 172 1 2018 not December 31, 2024.

Note 9 - In-process Research an

Note 9 - In-process Research and Development; Impairment Expense	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Asset Impairment Charges [Text Block]	Note 9. Scion Solutions Transaction dated March 1, 2022 On September 26, 2018, The consideration provided to Scion, which was subject to an escrow agreement dated September 26, 2018 ( December 31, 2021, Immediately following Clyra Medical’s purchase of Scion’s intangible assets, Clyra Medical sold to BioLargo the assets, along with 12,755 Clyra Medical common shares. In exchange, BioLargo issued Clyra Medical 7,142,858 shares of BioLargo common stock. Concurrently, BioLargo licensed back to Clyra Medical the Scion assets. Scion may 7,142,858 December 31, 2020, During the year ended December 31, 2020, first second December 31, 2020. December 31, 2020. By written agreement dated March 1, 2022, March 3, 2022, 2018 Spencer Brown and Tanya Rhodes each entered into non-disclosure agreements whereby they agreed not five not not Separately, BioLargo and Clyra Medical entered into an agreement dated March 3, 2022, March 1, 2022 Although these agreements were not March 3, 2022, first December 2021, 855, December 31, 2021. Impairment of Other Asset, Prepaid Marketing On December 30, 2015, four June 30, 2020, three not $788,000, Management determined as of December 31, 2021, The following table summarizes the expenses related to the foregoing transactions as of December 31, 2021. Biolargo Corporate Clyra Total In-Process Research and Development $ (2,150,000 ) $ — $ (2,150,000 ) Clyra debt obligations (Clyra-Scion note) — 1,007,000 1,007,000 Accounts payable and accrued interest — 458,000 458,000 Liability to Scion shareholders — 540,000 540,000 Other asset, prepaid marketing — (197,000 ) (197,000 ) Total $ (2,150,000 ) $ 1,808,000 $ (342,000 ) In light of Clyra Medical’s revenues for the year ended December 31, 2022, December 31, 2022,

Note 10 - Noncontrolling Intere

Note 10 - Noncontrolling Interest - Clyra Medical	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Noncontrolling Interest Disclosure [Text Block]	Note 10. Clyra Medical As discussed in Note 2 December 31, 2022. Debt Obligations of Clyra Medical Promissory Note On April 8, 2022, April 8, 2024, may Line of Credit On June 30, 2020, one one first 180 may On December 13, 2022, September 30, 2024, 14 As of December 31, 2022, $161,000. December 31, 2021, Equity Transactions As of December 31, 2022, Sales of Common Stock During the year ended December 31, 2022, not March 2, 2022, During the year ended December 31, 2021, Sales of Series A Preferred Stock On December 20, 2022, two one may Each investor also entered into an agreement with BioLargo whereby the investor may 20% 30 18 18 not June 30, 2023, Subsequent to December 31, 2022, 14 Stock Options Weighted Clyra average Options Exercise price per Outstanding price per share share Balance, December 31, 2020 11,411 $ 1.00 $ 1.00 Granted 2,594 1.00 1.00 Balance, December 31, 2021 14,004 $ 1.00 $ 1.00 Granted 1,829 1.00 - 310 40.24 Balance, December 31, 2022 15,833 $ 1.00 - 310 $ 5.53 Clyra issues options to its employees and consultants in lieu of compensation owed on a regular basis. During the years ended December 31, 2022 2021, December 31, 2021, December 31, 2022, $1.00 December 31, 2022 2021 no 3.83% Accounts Payable and Accrued Expenses At December 31, 2022 2021, Category 2022 2021 Accounts payable $ 186 $ 149 Accrued payroll 45 30 Accrued interest 7 51 Total $ 238 $ 230

Note 11 - BioLargo Engineering,

Note 11 - BioLargo Engineering, Science and Technologies, LLC	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Wholly-Owned Subsidiary [Text Block]	Note 11. In September 2017, three six 12 two no five five March 31, 2018 ( not first September 2018. The BLEST Compensation Committee has met regularly since the subsidiary commenced operations. In 2018, not not November 2019, one one not January 2021, one one one December 31, 2020. January 2022, one one December 31, 2021. December 2022, one one $135,000 December 31, 2022.

Note 12 - Business Segment Info

Note 12 - Business Segment Information	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Segment Reporting Disclosure [Text Block]	Note 12. BioLargo currently has four four 1. ONM Environmental -- which sells odor and volatile organic control products and services (located in Westminster, California); 2. Clyra Medical Technologies (“Clyra Medical”) -- which develops and sells medical products based on our technologies; 3. BLEST -- which provides professional engineering services on a time and materials basis for outside clients and supports our internal operations as needed (located in Oak Ridge, Tennessee); and 4. BioLargo Water (“Water”) -- which historically focused entirely on R&D, and has now shifted its focus to commercializing the AOS technology (located in Edmonton, Alberta Canada). Historically, none two 2022 third The segment information for the years December 31, 2022 2021, 2022 2021 Revenues BioLargo corporate $ 5 $ 7 ONM Environmental 4,374 1,419 BLEST 1,943 1,635 Clyra Medical 56 139 BioLargo Water 1 12 Intersegment revenue (495 ) (681 ) Total $ 5,884 $ 2,531 Research and development BioLargo corporate $ (674 ) $ (1,001 ) BLEST (469 ) (488 ) Clyra Medical (110 ) (66 ) BioLargo Water (565 ) (486 ) BioLargo corporate - intersegment 499 674 Total $ (1,319 ) $ (1,367 ) Operating income (loss) BioLargo corporate $ (3,971 ) $ (5,688 ) ONM Environmental 1,130 (511 ) BLEST (452 ) (629 ) Clyra Medical (1,383 ) 666 BioLargo Water (714 ) (616 ) Total $ (5,390 ) $ (6,778 ) Interest expense BioLargo corporate $ (24 ) $ (118 ) Clyra Medical (29 ) (116 ) Total $ (53 ) $ (234 ) Net income (loss) BioLargo corporate $ (3,995 ) $ (5,781 ) ONM Environmental 1,304 (511 ) BLEST (425 ) (629 ) Clyra Medical (1,412 ) 593 BioLargo Water (604 ) (566 ) Consolidated net loss $ (5,132 ) $ (6,894 ) As of December 31, 2022 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 669 $ 2,064 $ 631 $ 441 $ 194 $ (41 ) $ 3,958 Right of use 136 — — 731 — — 867 Investment in South Korean joint venture 33 — — — — — 33 Total $ 838 $ 2,064 $ 631 $ 1,172 $ 194 $ (41 ) $ 4,858 As of December 31, 2021 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 555 $ 451 $ 816 $ 595 $ 152 $ (47 ) $ 2,522 Right of use 222 — — 231 — — 453 Investment in South Korean joint venture 48 — — — — — 48 Total $ 825 $ 451 $ 816 $ 433 $ 152 $ (47 ) $ 3,023

Note 13 - Commitments and Conti

Note 13 - Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	Note 13. Office Leases We have long-term operating leases for office, industrial and laboratory space in Westminster, California, Oak Ridge, Tennessee, and Alberta, Canada. Payments made under operating leases are charged to the Consolidated Statement of Operations and Comprehensive Loss on a straight-line basis over the term of the operating lease agreement. Short-term leases less than one not December 31, 2022 2021, August 2024. four four not September 2022, ten ten December 31, 2022, one None no not no As of December 31, 2022, nine five Year ending BioLargo Corp / ONM BLEST Total December 31, 2023 118,000 151,000 269,000 December 31, 2024 70,000 154,000 224,000 December 31, 2025 -- 157,000 157,000 December 31, 2026 -- 160,000 160,000 December 31, 2027 -- 161,000 161,000 Thereafter -- 822,000 822,000 Total minimum lease payments $ 188,000 $ 1,605,000 $ 1,793,000

Note 14 - Subsequent Events

Note 14 - Subsequent Events	12 Months Ended
	Dec. 31, 2022
Notes to Financial Statements
Subsequent Events [Text Block]	Note 14. Management has evaluated subsequent events through the date of the filing of this Annual Report and management noted the following for disclosure. Lincoln Park Capital Purchase of Shares From January 1, 2023, March 29, 2023, 2022 3 $105,000 1 333 268973 Clyra Medical – Series A Preferred From January 1, 2023, March 29, 2023, three may 20% 30 18 18 not June 30, 2023, 10. Unit Offering From January 1, 2023, March 29, 2023, twelve six five BioLargo Energy Technologies, Inc. On January 1, 2023, January 1, 2023, March 29, 2023, March 29, 2023, Each investor also entered into an agreement with BioLargo whereby the investor may 20% 30 2024. one not Satisfaction of $50,000 On March 6, 2023, 4, March 1, 2023”) five CFO Engagement Extension On March 21, 2023, February 1, 2008 ( March 21, 2023 ( one January 31, 2024 ( As the sole compensation for the Extended Term, Mr. Dargan was issued an option (“Option”) to purchase 25,000 shares of the Company’s common stock for each month during the Extended Term (thus, an option to purchase 300,000 shares reflecting an extended term of 12 March 21, 2023, March 31, 2023, March 21, 2023 ten 2018 The Option is Mr. Dargan’s sole compensation for the Extended Term. As was the case in all prior terms of his engagement, there is no no not Clyra Medical On January 9, 2023, December 13, 2022. ( 10,

Significant Accounting Policies

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	Principles of Consolidation The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, and partially-owned subsidiaries BLEST and Clyra Medical. All intercompany accounts and transactions have been eliminated.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	Foreign Currency The Company has designated the functional currency of BioLargo Water, Inc., our Canadian subsidiary, to be the Canadian dollar. Therefore, translation gains and losses resulting from differences in exchange rates are recorded in accumulated other comprehensive income.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents The Company considers all highly liquid investments with maturities of three one $250,000 not As of December 31, 2022 2021, December 31, 2022 December 31, 2021 BioLargo, Inc. and subsidiaries $ 1,685 $ 941 Clyra Medical Technologies, Inc. 166 21 Total $ 1,851 $ 962
Receivable [Policy Text Block]	Accounts Receivable Trade accounts receivable are recorded net of allowances for doubtful accounts. Estimates for allowances for doubtful accounts are determined based on payment history and individual customer circumstances. The allowance for doubtful accounts as of December 31, 2022 2021 $ 12,000
Concentration Risk, Credit Risk, Policy [Policy Text Block]	Credit Concentration We have a limited number of customers that account for significant portions of our revenue. During the year ended December 31, 2022, two December 31, 2021, three December 31, 2022 December 31, 2021 Customer A 47 % <10 % Customer B 10 % <10 % Customer C <10 % 14 % Customer D <10 % 11 % Customer E <10 % 11 % We had one 10% December 31, 2022 two December 31, 2021, December 31, 2022 December 31, 2021 Customer A 24 % <10 % Customer F <10 % 32 % Customer G <10 % 12 %
Inventory, Policy [Policy Text Block]	Inventory Inventories are stated at the lower of cost or net realizable value using the average cost method. The allowance for obsolete inventory as of December 31, 2022 2021 $3,000. December 31, 2022 December 31, 2021 Raw material $ 46 $ 108 Finished goods 74 133 Total $ 120 $ 241
Other Assets, Policy [Policy Text Block]	Other Non-Current Assets Other non-current assets consisted of (i) security deposits related to our business offices, (ii) three October 22, 2021, December 31, 2022 December 31, 2021 Patents $ 34 $ 34 Security deposits 36 35 Tax credit receivable 54 — Total $ 124 $ 69
Equity Method Investments [Policy Text Block]	Equity Method of Accounting On March 20, 2020, We account for our investment in the joint venture under the equity method of accounting. We have determined that while we have significant influence over the joint venture through our technology license and our position on the Board of Directors, we do not December 31, 2022 2021,
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	Impairment Long-lived and definite lived intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not For the year ended December 31, 2022, 9 For the year ended December 31, 2021, 9 9 December 31, 2022 2021 $342,000,
Earnings Per Share, Policy [Policy Text Block]	Earnings (Loss) Per Share We report basic and diluted earnings (loss) per share (“EPS”) for common and common share equivalents. Basic EPS is computed by dividing reported earnings by the weighted average shares outstanding. Diluted EPS is computed by adding to the weighted average shares the dilutive effect if convertible notes payable, stock options and warrants were exercised into common stock. For the years ended December 31, 2022 2021,
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and revenues and expenses during the period reported. Actual results could differ from those estimates. Estimates are used when accounting for stock-based transactions, debt transactions, derivative liabilities, allowance for bad debt, asset depreciation and amortization, impairment expense, among others. The methods, estimates and judgments we use in applying these most critical accounting policies have a significant impact on the results of our financial statements.
Share-Based Payment Arrangement [Policy Text Block]	Share-Based Compensation Expense We recognize compensation expense for stock option awards on a straight-line basis over the applicable service period of the award, which is the vesting period. Fair value is determined on the grant date. Share-based compensation expense is based on the grant date fair value estimated using the Black-Scholes Option Pricing Model. For stock and stock options issued to consultants and other non-employees for services, the Company measures and records an expense as of the earlier of the date at which either: a commitment for performance by the non-employee has been reached or the non-employee’s performance is complete. The equity instruments are measured at the current fair value, and for stock options, the instruments are measured at fair value using the Black Scholes option model. The following methodology and assumptions were used to calculate share-based compensation for the years ended December 31, 2022 2021: 2022 2021 Non Plan 2018 Plan Non Plan 2018 Plan Risk free interest rate 2.32 – 3.83 % 2.32 – 3.83 % 1.49 – 1.73 % 0.93 – 1.73 % Expected volatility 114 – 117 % 114 – 117 % 118 – 124 % 118 – 124 % Expected dividend yield — — — — Forfeiture rate — — — — Life in years 10 10 10 10 Expected price volatility is the measure by which our stock price is expected to fluctuate during the expected term of an option. Expected volatility is derived from the historical daily change in the market price of our common stock, as we believe that historical volatility is the best indicator of future volatility. The risk-free interest rate used in the Black-Scholes calculation is based on the prevailing U.S. Treasury yield as determined by the U.S. Federal Reserve. We have never paid any cash dividends on our common stock and do not
Warrant Policy [Policy Text Block]	Warrants Warrants issued with our convertible and non-convertible debt instruments are accounted for under the fair value and relative fair value method. The warrant is first not. not If the warrant is determined to not Convertible debt instruments are recorded at fair value, limited to a relative fair value based upon the percentage of its fair value to the total fair value including the fair value of the warrant. The warrant relative fair values are also recorded as a discount to the convertible promissory notes. As present, these equity features of the convertible promissory notes have recorded a discount to the convertible notes that is substantially equal to the proceeds received.
Non Cash Transactions [Policy Text Block]	Non-Cash Transactions We have established a policy relative to the methodology to determine the value assigned to each intangible we acquire, and/or services or products received for non-cash consideration of our common stock. The value is based on the market price of our common stock issued as consideration, at the date of the agreement of each transaction or when the service is rendered or product is received.
Revenue from Contract with Customer [Policy Text Block]	Revenue Recognition We account for revenue in accordance with ASC 606, Step 1: Identify the contract(s) with a customer. Step 2: Identify the performance obligations in the contract. Step 3: Determine the transaction price. Step 4: Allocate the transaction price to the performance obligations in the contract. Step 5: Recognize revenue when (or as) the entity satisfies a performance obligation. The Company’s products are sold through a contract with the customer and a written purchase order, in which the details of the contract are defined including the transaction price and method of shipment. The only performance obligation is to create and ship the product, and each product has separate pricing. Revenue is recognized at a point in time when the goods are shipped if the agreement is FOB manufacturer, and when goods are delivered if FOB destination. Revenue is recognized with a reduction for sales discounts, as appropriate and negotiated in the customer’s purchase order. Service contracts are performed through a written contract, which specifies the performance obligations and the rate at which the services will be billed, typically by time and materials. Each service is separately negotiated and priced. Revenue is recognized as services are performed and completed, or, for services related to product installations, at the completion of the installation. A few contracts have called for milestone or fixed cost payments, where we invoice an agreed-to amount per month for the life of the contract. In these instances, completed work, billed hourly, is recognized as revenue. If the billing amount is greater or lesser than the completed work, a receivable or payable is created. These accounts are adjusted upon additional billings as the work is completed. To date, there have been no In the event that we generate revenues from royalties or license fees from our intellectual property, we anticipate a licensee would pay a license fee in one Clyra also has certain distribution agreements that call for consigned inventory. Although the product is shipped to a third not
Government Grants [Policy Text Block]	Government Grants We have been awarded multiple research grants from the private and public Canadian research programs. Income we receive directly from grants is recorded as other income. We have been awarded over 80 first 2015. third third six eighteen not The grants typically provide for (i) recurring monthly amounts, (ii) reimbursement of costs for research talent for which we invoice to request payment, and (iii) ancillary cost reimbursement for research talent travel related costs. All awarded grants have specific requirements on how the money is spent, typically to employ researchers. None may Not no
Income Tax, Policy [Policy Text Block]	Income Taxes The asset and liability approach is used to recognize deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of asset and liabilities. Deferred tax assets and liabilities are determined based on the differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The effect on deferred tax asset and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. We account for uncertainties in income tax law under a comprehensive model for the financial statement recognition, measurement, presentation and disclosure of uncertain tax positions taken or expected to be taken in income tax returns as prescribed by generally accepted accounting principles (“GAAP”). Under GAAP, the tax effects of a position are recognized only if it is “more-likely-than- not” not not” no December 31, 2022 2021. The Company assessed its earnings history, trends and estimates of future earnings and determined that the deferred tax asset could not December 31, 2022. The Company recognizes interest and penalties on income taxes as a component of income tax expense, should such an expense be realized.
Fair Value of Financial Instruments, Policy [Policy Text Block]	Fair Value of Financial Instruments Management believes the carrying amounts of the Company’s financial instruments as of December 31, 2022 2021
Tax Credits [Policy Text Block]	Tax Credits Our research and development activities in Canada may not
Lessee, Leases [Policy Text Block]	Leases In February 2016, No. 2016 02, 11 January 1, 2019 July 2018, may 842, December 31, 2022, $867,000
Property, Plant and Equipment, Policy [Policy Text Block]	Equipment Equipment is stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, which range from 3 - 5
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements None.

Note 2 - Summary of Significa_2

Note 2 - Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Schedule of Cash and Cash Equivalents [Table Text Block]	December 31, 2022 December 31, 2021 BioLargo, Inc. and subsidiaries $ 1,685 $ 941 Clyra Medical Technologies, Inc. 166 21 Total $ 1,851 $ 962
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	December 31, 2022 December 31, 2021 Customer A 47 % <10 % Customer B 10 % <10 % Customer C <10 % 14 % Customer D <10 % 11 % Customer E <10 % 11 % December 31, 2022 December 31, 2021 Customer A 24 % <10 % Customer F <10 % 32 % Customer G <10 % 12 %
Schedule of Inventory, Current [Table Text Block]	December 31, 2022 December 31, 2021 Raw material $ 46 $ 108 Finished goods 74 133 Total $ 120 $ 241
Schedule of Other Assets, Noncurrent [Table Text Block]	December 31, 2022 December 31, 2021 Patents $ 34 $ 34 Security deposits 36 35 Tax credit receivable 54 — Total $ 124 $ 69
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	2022 2021 Non Plan 2018 Plan Non Plan 2018 Plan Risk free interest rate 2.32 – 3.83 % 2.32 – 3.83 % 1.49 – 1.73 % 0.93 – 1.73 % Expected volatility 114 – 117 % 114 – 117 % 118 – 124 % 118 – 124 % Expected dividend yield — — — — Forfeiture rate — — — — Life in years 10 10 10 10

Note 4 - Debt Obligations (Tabl

Note 4 - Debt Obligations (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Schedule of Debt [Table Text Block]	December 31, 2022 2021 Current portion of debt: SBA Paycheck Protection Program loan $ 43 $ 314 Convertible note payable, matures March 1, 2023 50 — SBA EIDL Loan, matures July 2053, current portion 10 — Debt discount, net of amortization (3 ) — Total current portion of debt $ 100 $ 314 Long-term debt: SBA Paycheck Protection Program loans, matures May 2025 $ 97 $ — Convertible note payable, matures March 1, 2023 — 50 Debt discount, net of amortization — (20 ) SBA EIDL Loan, matures July 2053 140 150 Total long-term debt, net of current $ 237 $ 180 Total $ 337 $ 494

Note 5 - Share-based Compensa_2

Note 5 - Share-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Weighted Average Aggregate Options Exercise Price per Intrinsic Outstanding Price per share share Value (1) Balance, December 31, 2020 18,865,525 $0.12 – 0.43 $ 0.19 Granted 4,320,617 $0.13 – 0.23 $ 0.19 Balance, December 31, 2021 23,186,142 $0.12 – 0.43 $ 0.19 Granted 6,322,233 $0.18 – 0.27 $ 0.22 Exercised (290,243 ) $0.13 – 0.23 $ 0.16 Expired (733,583 ) $0.12 – 0.40 $ 0.33 Balance, December 31, 2022 28,484,549 $0.12 – 0.43 $ 0.19 Non-vested (3,746,708 ) $0.18 – 0.27 $ 0.19 Vested, December 31, 2022 24,737,841 $0.12 – 0.43 $ 0.19 $ 596,000 Weighted Average Aggregate Options Exercise Price per intrinsic Outstanding price per share share Value (1) Balance, December 31, 2020 5,689,363 $ 0.23 – 0.94 $ 0.44 Expired (2,810,117 ) 0.34 – 0.51 0.38 Balance, December 31, 2021 2,879,246 $ 0.23 – 0.94 $ 0.49 Expired (975,161 ) 0.35 – 0.40 0.36 Balance, December 31, 2022 1,904,085 $ 0.23 – 0.94 $ 0.56 $ — Weighted Non-plan average Aggregate Options Exercise price per intrinsic outstanding price per share share value (1) Balance, December 31, 2020 20,749,583 $ 0.12 – 1.00 $ 0.41 Granted 169,624 0.17 – 0.23 0.20 Expired (800,000 ) 1.00 1.00 Balance, December 31, 2021 20,119,207 $ 0.12 – 0.83 $ 0.39 Granted 571,358 0.17 – 0.27 0.19 Expired (1,666,736 ) 0.30 – 0.40 0.31 Balance, December 31, 2022 19,023,829 $ 0.12 – 0.83 $ 0.39 Unvested (507,500 ) 0.45 0.45 Vested and outstanding, December 31, 2022 18,516,329 $ 0.12 – 0.83 $ 0.39 $ 77,000

Note 6 - Warrants (Tables)

Note 6 - Warrants (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]	Weighted average Aggregate Warrants Exercise price per intrinsic outstanding price per share share value (1) Balance, December 31, 2020 32,980,989 $ 0.13 – 1.00 $ 0.29 Granted 11,096,992 0.12 – 0.14 0.21 Exercised (1,283,333 ) 0.12 – 0.14 0.13 Expired (6,029,086 ) 0.12 – 0.70 0.30 Balance, December 31, 2021 36,765,562 $ 0.13 – 1.00 $ 0.27 Granted 27,137,048 0.12 – 0.14 0.23 Exercised — Expired (14,879,152 ) 0.12 – 0.48 0.24 Balance, December 31, 2022 49,023,398 $ 0.13 – 1.00 $ 0.26 $ 691,000
Schedule Of Assumptions Used To Determine Fair Value Of Warrants [Table Text Block]	2022 2021 Risk free interest rate 3.69 – 3.88% 0.71% Expected volatility 40% 100% Expected dividend yield — — Forfeiture rate — — Expected life in years 3 .5 – 5

Note 7 - Accounts Payable and_2

Note 7 - Accounts Payable and Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	Category BioLargo ONM BLEST Water Intercompany amounts Totals Accounts payable $ 187 $ 486 $ 7 $ 119 $ (82 ) $ 717 Accrued payroll 20 58 120 — — 198 Accrued interest 25 — — — — 25 Total $ 940 Category BioLargo ONM BLEST Water Intercompany amounts Totals Accounts payable $ 156 $ 72 $ 73 $ 96 $ (47 ) $ 350 Accrued payroll 37 53 94 — — 184 Accrued interest 25 — — — — 25 Total $ 559

Note 9 - In-process Research _2

Note 9 - In-process Research and Development; Impairment Expense (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Impairment Expense Disclosure [Table Text Block]	Biolargo Corporate Clyra Total In-Process Research and Development $ (2,150,000 ) $ — $ (2,150,000 ) Clyra debt obligations (Clyra-Scion note) — 1,007,000 1,007,000 Accounts payable and accrued interest — 458,000 458,000 Liability to Scion shareholders — 540,000 540,000 Other asset, prepaid marketing — (197,000 ) (197,000 ) Total $ (2,150,000 ) $ 1,808,000 $ (342,000 )

Note 10 - Noncontrolling Inte_2

Note 10 - Noncontrolling Interest - Clyra Medical (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Schedule of Other Ownership Interests [Table Text Block]	Weighted Clyra average Options Exercise price per Outstanding price per share share Balance, December 31, 2020 11,411 $ 1.00 $ 1.00 Granted 2,594 1.00 1.00 Balance, December 31, 2021 14,004 $ 1.00 $ 1.00 Granted 1,829 1.00 - 310 40.24 Balance, December 31, 2022 15,833 $ 1.00 - 310 $ 5.53
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	Category BioLargo ONM BLEST Water Intercompany amounts Totals Accounts payable $ 187 $ 486 $ 7 $ 119 $ (82 ) $ 717 Accrued payroll 20 58 120 — — 198 Accrued interest 25 — — — — 25 Total $ 940 Category BioLargo ONM BLEST Water Intercompany amounts Totals Accounts payable $ 156 $ 72 $ 73 $ 96 $ (47 ) $ 350 Accrued payroll 37 53 94 — — 184 Accrued interest 25 — — — — 25 Total $ 559
Clyra Medical [Member]
Notes Tables
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	Category 2022 2021 Accounts payable $ 186 $ 149 Accrued payroll 45 30 Accrued interest 7 51 Total $ 238 $ 230

Note 12 - Business Segment In_2

Note 12 - Business Segment Information (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Schedule of Segment Reporting Information, by Segment [Table Text Block]	2022 2021 Revenues BioLargo corporate $ 5 $ 7 ONM Environmental 4,374 1,419 BLEST 1,943 1,635 Clyra Medical 56 139 BioLargo Water 1 12 Intersegment revenue (495 ) (681 ) Total $ 5,884 $ 2,531 Research and development BioLargo corporate $ (674 ) $ (1,001 ) BLEST (469 ) (488 ) Clyra Medical (110 ) (66 ) BioLargo Water (565 ) (486 ) BioLargo corporate - intersegment 499 674 Total $ (1,319 ) $ (1,367 ) Operating income (loss) BioLargo corporate $ (3,971 ) $ (5,688 ) ONM Environmental 1,130 (511 ) BLEST (452 ) (629 ) Clyra Medical (1,383 ) 666 BioLargo Water (714 ) (616 ) Total $ (5,390 ) $ (6,778 ) Interest expense BioLargo corporate $ (24 ) $ (118 ) Clyra Medical (29 ) (116 ) Total $ (53 ) $ (234 ) Net income (loss) BioLargo corporate $ (3,995 ) $ (5,781 ) ONM Environmental 1,304 (511 ) BLEST (425 ) (629 ) Clyra Medical (1,412 ) 593 BioLargo Water (604 ) (566 ) Consolidated net loss $ (5,132 ) $ (6,894 ) As of December 31, 2022 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 669 $ 2,064 $ 631 $ 441 $ 194 $ (41 ) $ 3,958 Right of use 136 — — 731 — — 867 Investment in South Korean joint venture 33 — — — — — 33 Total $ 838 $ 2,064 $ 631 $ 1,172 $ 194 $ (41 ) $ 4,858 As of December 31, 2021 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 555 $ 451 $ 816 $ 595 $ 152 $ (47 ) $ 2,522 Right of use 222 — — 231 — — 453 Investment in South Korean joint venture 48 — — — — — 48 Total $ 825 $ 451 $ 816 $ 433 $ 152 $ (47 ) $ 3,023

Note 13 - Commitments and Con_2

Note 13 - Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2022
Notes Tables
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	Year ending BioLargo Corp / ONM BLEST Total December 31, 2023 118,000 151,000 269,000 December 31, 2024 70,000 154,000 224,000 December 31, 2025 -- 157,000 157,000 December 31, 2026 -- 160,000 160,000 December 31, 2027 -- 161,000 161,000 Thereafter -- 822,000 822,000 Total minimum lease payments $ 188,000 $ 1,605,000 $ 1,793,000

Note 1 - Business and Organiz_2

Note 1 - Business and Organization (Details Textual)	11 Months Ended	12 Months Ended		24 Months Ended
	Dec. 13, 2022 USD ($) shares	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2022 USD ($)	Sep. 30, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total		$ (5,132,000)	$ (6,894,000)
Net Cash Provided by (Used in) Operating Activities, Total		(2,762,000)	(3,937,000)
Working Capital (Deficit)		1,587,000		$ 1,587,000
Assets, Current, Total		3,153,000	1,801,000	3,153,000
Revenue from Contract with Customer, Including Assessed Tax		5,884,000	2,531,000
Proceeds from Issuance of Common Stock		3,617,000	4,882,000
Cash and Cash Equivalents, at Carrying Value, Total		$ 1,851,000	$ 962,000	$ 1,851,000
Number of Wholly-Owned Subsidiaries		6		6
BioLargo Engineering, Science & Technologies, LLC [Member]
Noncontrolling Interest, Ownership Percentage by Parent		82%		82%	100%
Clyra Medical Technologies [Member]
Noncontrolling Interest, Ownership Percentage by Parent		58%		58%
Subsidiary, Clyra Medical [Member]
Notes Payable, Related Parties		$ 261,000		$ 261,000
Economic Injury Disaster Loan [Member]
Convertible Debt, Total		50,000		50,000
Long-Term Debt, Total		150,000		$ 150,000
Debt Instrument, Term (Year)				30 years
Paycheck Protection Program CARES Act [Member]
Long-Term Debt, Total		140,000		$ 140,000
Warrant Issued to Private Investors [Member]
Proceeds from Issuance of Common Stock		$ 2,364,000
Class of Warrant or Right, Issued During Period, Number of Securities Called by Warrants or Rights (in shares) | shares		27,137,048
The 2020 Unit Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares		13,568,524	5,435,966
Proceeds from Issuance of Common Stock		$ 2,364,000	$ 864,000
Lincoln Park Capital Fund, LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares	6,011,701	6,011,701	24,255,920
Proceeds from Issuance of Common Stock	$ 1,253,000	$ 1,253,000	$ 4,018,000

Note 2 - Summary of Significa_3

Note 2 - Summary of Significant Accounting Policies (Details Textual)		12 Months Ended
	Mar. 20, 2020 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)	Jan. 19, 2019 USD ($)
Accounts Receivable, Allowance for Credit Loss, Current		$ 12,000	$ 12,000
Inventory Valuation Reserves		158,000	3,000
Payments to Acquire Intangible Assets		0	13,000
Income (Loss) from Equity Method Investments		(15,000)	(15,000)
Impairment, Long-Lived Asset, Held-for-Use, Total		197,000	342,000
Unrecognized Tax Benefits, Ending Balance		0	0
Operating Lease, Right-of-Use Asset		867,000	$ 453,000	$ 399,000
Operating Lease, Liability, Total		$ 870,000
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)		3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)		5 years
Canadian Government Grants [Member] | Minimum [Member]
Grant Term (Month)		6 months
Canadian Government Grants [Member] | Maximum [Member]
Grant Term (Month)		18 months
Odin Co Ltd [Member]
Payments to Acquire Interest in Joint Venture	$ 100,000
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	40%	40%	40%
Income (Loss) from Equity Method Investments		$ (15,000)
Odin Co Ltd [Member] | Tomorrow Water [Member]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	30%
Odin Co Ltd [Member] | BKT and Tomorrow Water [Member]
Payments to Acquire Interest in Joint Venture	$ 150,000
Patents [Member]
Intangible Assets, Net (Excluding Goodwill), Total		34,000
Payments to Acquire Intangible Assets		13,000
Intangible Assets, Remaining Balance After Cash Payment Amount		$ 21,000
Stock Issued During Period, Shares, Issued for Intangible Assets Purchase (in shares) | shares		125,000
Shares Issued, Price Per Share (in dollars per share) | $ / shares		$ 0.17
Customer Concentration Risk [Member] | Revenue from Contract with Customer Benchmark [Member]
Number of Major Customers		2	3
Customer Concentration Risk [Member] | Revenue from Contract with Customer Benchmark [Member] | Two Customers [Member]
Concentration Risk, Percentage		10%
Customer Concentration Risk [Member] | Revenue from Contract with Customer Benchmark [Member] | Three Customers [Member]
Concentration Risk, Percentage			10%
Customer Concentration Risk [Member] | Revenue from Contract with Customer Benchmark [Member] | One Customer [Member]
Number of Major Customers		1
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Number of Major Customers			2
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Two Customers [Member]
Concentration Risk, Percentage			10%

Note 2 - Summary of Significa_4

Note 2 - Summary of Significant Accounting Policies - Summary of Cash Balances (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents, at Carrying Value, Total	$ 1,851,000	$ 962,000
Parent Company [Member]
Cash and Cash Equivalents, at Carrying Value, Total	1,685,000	941,000
Noncontrolling Interest [Member]
Cash and Cash Equivalents, at Carrying Value, Total	$ 166,000	$ 21,000

Note 2 - Summary of Significa_5

Note 2 - Summary of Significant Accounting Policies - Credit Concentration (Details) - Customer Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Customer A [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	47%	10%
Customer A [Member] | Accounts Receivable [Member]
Credit concentration	24%	10%
Customer B [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	10%	10%
Customer F [Member] | Accounts Receivable [Member]
Credit concentration	10%	32%
Customer C [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	10%	14%
Customer G [Member] | Accounts Receivable [Member]
Credit concentration	10%	12%
Customer D [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	10%	11%
Customer E [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	10%	11%

Note 2 - Summary of Significa_6

Note 2 - Summary of Significant Accounting Policies - Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Raw material	$ 46	$ 108
Finished goods	74	133
Total	$ 120	$ 241

Note 2 - Summary of Significa_7

Note 2 - Summary of Significant Accounting Policies - Other Non-current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Patents	$ 34	$ 34
Security deposits	36	35
Tax credit receivable	54	0
Total	$ 124	$ 69

Note 2 - Summary of Significa_8

Note 2 - Summary of Significant Accounting Policies - Stock Options, Valuation Assumptions (Details)	12 Months Ended	24 Months Ended
	Dec. 31, 2022	Dec. 31, 2022
Non Plan [Member]
Risk free interest rate		0.93%
Expected volatility		118%
Expected dividend yield	0%	0%
Forfeiture rate	0%	0%
Life in years (Year)	10 years	10 years
Non Plan [Member] | Minimum [Member]
Risk free interest rate	2.32%
Expected volatility	114%
Non Plan [Member] | Maximum [Member]
Risk free interest rate	2.32%
Expected volatility	114%
2018 Equity Incentive Plan [Member]
Expected dividend yield	0%
Forfeiture rate	0%
Life in years (Year)	10 years
2018 Equity Incentive Plan [Member] | Minimum [Member]
Risk free interest rate	3.83%	1.73%
Expected volatility	117%	124%
2018 Equity Incentive Plan [Member] | Maximum [Member]
Risk free interest rate	1.73%
Expected volatility	124%

Note 3 - Sale of Stock for Ca_2

Note 3 - Sale of Stock for Cash (Details Textual) - USD ($)	11 Months Ended	12 Months Ended
	Dec. 13, 2022	Dec. 31, 2022	Dec. 31, 2021
Stock Issued During Period, Value, Commitment Fee		$ 0
Proceeds from Issuance of Common Stock		$ 3,617,000	$ 4,882,000
Warrants Issued with 2020 Unit Offering [Member] | Maximum [Member]
Warrants and Rights Outstanding, Term (Year)		5 years	5 years
Warrants Issued with 2020 Unit Offering [Member] | Minimum [Member]
Warrants and Rights Outstanding, Term (Year)		6 months	6 months
The 2020 Unit Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)		13,568,524	5,435,966
Proceeds from Issuance of Common Stock		$ 2,364,000	$ 864,000
Lincoln Park Capital Fund, LLC [Member]
Stock Purchase Agreement, Maximum Amount of Common Stock	$ 10,000,000
Stock Issued During Period, Shares, Commitment Fee (in shares)	1,250,000
Stock Issued During Period, Value, Commitment Fee	$ 240,000
Stock Issued During Period, Shares, New Issues (in shares)	6,011,701	6,011,701	24,255,920
Proceeds from Issuance of Common Stock	$ 1,253,000	$ 1,253,000	$ 4,018,000

Note 4 - Debt Obligations (Deta

Note 4 - Debt Obligations (Details Textual) - USD ($)							1 Months Ended	4 Months Ended	12 Months Ended
	May 12, 2022	Feb. 07, 2022	Aug. 13, 2021	Apr. 20, 2021	Mar. 01, 2021	Mar. 08, 2018	Apr. 30, 2020	Jul. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Interest Expense, Debt, Total									$ 53,000	$ 234,000
Repayments of Long-term Lines of Credit									26,000	37,000
Debt Conversion, Original Debt, Amount									0	$ 328,000
Convertible Note, Maturing August 12, 2021 [Member]
Repayments of Convertible Debt			$ 178,000
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)			1,272,321
Convertible Debt, Total			$ 228,000
Convertible Note, Maturing August 9, 2021 [Member]
Repayments of Convertible Debt					$ 600,000
Line of Credit, Maturing September 1, 2019 [Member]
Repayments of Long-term Lines of Credit					50,000
Long-term Line of Credit, Total									0
Promissory Note, Maturing on April 20, 2021 [Member] | Conversion of Debt into Shares of Common Stock [Member]
Debt Conversion, Original Debt, Amount				$ 100,000
Debt Conversion, Converted Instrument, Shares Issued (in shares)				400,000
Promissory Note, Maturing on April 20, 2021 [Member] | Conversion of Debt Accrued Interest into Shares of Common Stock [Member]
Debt Conversion, Original Debt, Amount				$ 9,994
Debt Conversion, Converted Instrument, Shares Issued (in shares)				48,706
Note Payable, Maturing March 8, 2023 [Member]
Proceeds from Notes Payable, Total						$ 50,000
Debt Instrument, Face Amount					$ 50,000						$ 50,000
Debt Instrument, Convertible, Conversion Price (in dollars per share)					$ 0.16
Paycheck Protection Program CARES Act [Member] | ONM [Member]
Extinguishment of Debt, Amount		$ 174,000
Proceeds from Issuance of Debt		$ 217,243
Paycheck Protection Program CARES Act [Member] | BELST [Member]
Proceeds from Issuance of Debt	$ 97,000
Paycheck Protection Program CARES Act [Member] | Clyra Medical [Member]
Proceeds from Issuance of Debt							$ 43,000
Economic Injury Disaster Loan [Member]
Convertible Debt, Total									$ 50,000
Economic Injury Disaster Loan [Member] | ONM [Member]
Debt Instrument, Face Amount								$ 150,000
Debt Instrument, Interest Rate, Stated Percentage								3.75%
Debt Instrument, Periodic Payment, Total								$ 800

Note 4 - Debt Obligations - Sch

Note 4 - Debt Obligations - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
SBA EIDL Loan, matures July 2053, current portion	$ 100	$ 314
Debt discount, net of amortization	(3)	0
Total current portion of debt	100	314
Long-term debt	237	180
Debt discount, net of amortization	0	(20)
Total	337	494
Paycheck Protection Program CARES Act [Member]
SBA Paycheck Protection Program loan	43	314
SBA Paycheck Protection Program loans, matures May 2025	97	0
Convertible Note, Maturing On March 1, 2023 [Member]
Convertible notes	50	0
Long-term debt	0	50
Economic Injury Disaster Loan [Member]
SBA EIDL Loan, matures July 2053, current portion	10	0
Long-term debt	$ 140	$ 150

Note 5 - Share-based Compensa_3

Note 5 - Share-based Compensation (Details Textual) - USD ($)												1 Months Ended	12 Months Ended
	Dec. 30, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Mar. 22, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 22, 2018	Sep. 07, 2017	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 20, 2022
Stock Issued During Period, Value, Issued for Services													$ 291,000	$ 367,000
Stock Issued During Period, Value, New Issues													$ 3,617,000	$ 4,882,000
Share Price (in dollars per share)						$ 0.20							$ 0.20	$ 0.20
2018 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)										10 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)										40,000,000			48,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Per Year (in shares)										2,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													6,322,233	4,320,617
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.22	$ 0.19
The 2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)											10 years
Non Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													571,358	169,624
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.19
Clyra Medical [Member]
Shares Issued, Price Per Share (in dollars per share)						$ 310							$ 310	$ 310	$ 310
Stock Issued During Period, Value, New Issues														$ 50,000
Stock Issued During Period, Shares, New Issues (in shares)														161
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													1,829	2,594
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 40.24	$ 1
Share-Based Payment Arrangement, Option [Member] | Clyra Medical [Member]
Share-Based Payment Arrangement, Expense													$ 408,000	$ 564,000
Selling, General and Administrative Expenses [Member]
Share-Based Payment Arrangement, Expense													2,071,000	1,872,000
Common Stock Issued for Accrued Interest Due on Promissory Note [Member]
Shares Issued, Price Per Share (in dollars per share)								$ 0.19				$ 0.19
Stock Issued During Period, Value, New Issues												$ 16,000
Stock Issued During Period, Shares, New Issues (in shares)												81,777
Officer [Member]
Stock Issued During Period, Value, Issued for Services													$ 120,000	$ 46,000
Stock Issued During Period, Shares, Issued for Services (in shares)		268,330	263,895			15,000	61,842		137,364				532,225	214,206
Shares Issued, Price Per Share (in dollars per share)		$ 0.27	$ 0.18			$ 0.21	$ 0.19		$ 0.23					$ 0.21
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Minimum Cash Amount Receipt													$ 3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Minimum Revenue Required													3,000,000
Consultants [Member]
Stock Issued During Period, Value, Issued for Services													$ 171,000	$ 282,000
Stock Issued During Period, Shares, Issued for Services (in shares)	642,041	110,498	76,996	86,752		348,772	586,963	367,403	610,123				916,287	1,913,261
Shares Issued, Price Per Share (in dollars per share)	$ 0.20	$ 0.27	$ 0.18	$ 0.23		$ 0.21	$ 0.19	$ 0.16	$ 0.23			$ 0.16		$ 0.21
Employees, Consultants, Officers, and Directors [Member] | 2018 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													6,322,233
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value													$ 1,329,000
CFO and President [Member] | 2018 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													495,135
Chief Financial Officer [Member] | 2018 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)					10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)					300,000								300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value													$ 68,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)					$ 0.24								$ 0.17
Term Extension (Year)					1 year
Share-based Compensation Arrangement By Share-based Payment Award, Options Grants Per Month, Gross (in shares)					25,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares (in shares)					25,000
President [Member] | 2018 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value													$ 97,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.23
Board Of Directors [Member] | 2018 Equity Incentive Plan [Member]
Share-Based Payment Arrangement, Expense													$ 401,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													1,861,456
Board Of Directors [Member] | 2018 Equity Incentive Plan [Member] | Minimum [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.18
Board Of Directors [Member] | 2018 Equity Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.27
Employees [Member] | 2018 Equity Incentive Plan [Member]
Share-Based Payment Arrangement, Expense													$ 608,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													2,933,901
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)													4 years
Employees [Member] | 2018 Equity Incentive Plan [Member] | Minimum [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.18
Employees [Member] | 2018 Equity Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)													$ 0.27
Employees and Consultants [Member] | 2018 Equity Incentive Plan [Member]
Stock Issued During Period, Value, Issued for Services													$ 155,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													731,741
Employees and Consultants [Member] | Clyra Medical [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)													10 years
Vendors [Member] | Non Plan [Member]
Share-Based Payment Arrangement, Expense													$ 109,000	$ 34,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)													571,358	169,624
Vendors [Member] | Non Plan [Member] | Minimum [Member]
Shares Issued, Price Per Share (in dollars per share)						0.17							$ 0.17	$ 0.17
Vendors [Member] | Non Plan [Member] | Maximum [Member]
Shares Issued, Price Per Share (in dollars per share)						$ 0.23							$ 0.27	$ 0.23

Note 5 - Share-based Compensa_4

Note 5 - Share-based Compensation - Stock Options (Details) - USD ($)		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021
2018 Equity Incentive Plan [Member]
Options outstanding, balance (in shares)		23,186,142	18,865,525
Balance (in dollars per share)		$ 0.19	$ 0.19
Options granted (in shares)		6,322,233	4,320,617
Granted (in dollars per share)		$ 0.22	$ 0.19
Options Exercised (in shares)		(290,243)
Exercised (in dollars per share)		$ 0.16
Options expired (in shares)		(733,583)
Expired (in dollars per share)		$ 0.33
Options outstanding, balance (in shares)		28,484,549	23,186,142
Balance (in dollars per share)		$ 0.19	$ 0.19
Options Non-vested (in shares)		(3,746,708)
Non-vested (in dollars per share)		$ 0.19
Options Vested (in shares)		24,737,841
Vested, December 31, 2022 (in dollars per share)		$ 0.19
Vested, December 31, 2022	[1]	$ 596,000
2018 Equity Incentive Plan [Member] | Minimum [Member]
Exercise price per share, balance (in dollars per share)		$ 0.12	0.12
Exercise price per share, granted (in dollars per share)		0.18	0.13
Exercise price per share, Exercised (in dollars per share)		0.13
Exercise price per share, Expired (in dollars per share)		0.12
Exercise price per share, balance (in dollars per share)		0.12	0.12
Exercise price per share, Non-vested (in dollars per share)		0.18
Exercise price per share, Vested (in dollars per share)		0.12
2018 Equity Incentive Plan [Member] | Maximum [Member]
Exercise price per share, balance (in dollars per share)		0.43	0.43
Exercise price per share, granted (in dollars per share)		0.27	0.23
Exercise price per share, Exercised (in dollars per share)		0.23
Exercise price per share, Expired (in dollars per share)		0.40
Exercise price per share, balance (in dollars per share)		0.43	$ 0.43
Exercise price per share, Non-vested (in dollars per share)		0.27
Exercise price per share, Vested (in dollars per share)		$ 0.43
The 2007 Equity Incentive Plan [Member]
Options outstanding, balance (in shares)		2,879,246	5,689,363
Balance (in dollars per share)		$ 0.49	$ 0.44
Options expired (in shares)		(975,161)	(2,810,117)
Expired (in dollars per share)		$ 0.36	$ 0.38
Options outstanding, balance (in shares)		1,904,085	2,879,246
Balance (in dollars per share)		$ 0.56	$ 0.49
The 2007 Equity Incentive Plan [Member] | Minimum [Member]
Balance (in dollars per share)		0.23	0.23
Expired (in dollars per share)		0.35	0.34
Balance (in dollars per share)		0.23	0.23
The 2007 Equity Incentive Plan [Member] | Maximum [Member]
Balance (in dollars per share)		0.94	0.94
Expired (in dollars per share)		0.40	0.51
Balance (in dollars per share)		$ 0.94	$ 0.94
Non Plan [Member]
Options outstanding, balance (in shares)		20,119,207	20,749,583
Balance (in dollars per share)			$ 0.41
Options granted (in shares)		571,358	169,624
Granted (in dollars per share)		$ 0.19
Options expired (in shares)		(1,666,736)	(800,000)
Expired (in dollars per share)		$ 0.31	$ 1
Options outstanding, balance (in shares)		19,023,829	20,119,207
Options Non-vested (in shares)		(507,500)
Non-vested (in dollars per share)		$ 0.45
Options Vested (in shares)		18,516,329
Vested, December 31, 2022 (in dollars per share)		$ 0.39
Vested, December 31, 2022		$ 77,000
Non Plan [Member] | Minimum [Member]
Exercise price per share, balance (in dollars per share)		$ 0.12	$ 0.12
Exercise price per share, granted (in dollars per share)		0.17	0.17
Exercise price per share, Expired (in dollars per share)		0.30	1
Exercise price per share, balance (in dollars per share)			0.12
Exercise price per share, Non-vested (in dollars per share)		0.45
Exercise price per share, Vested (in dollars per share)		0.12
Non Plan [Member] | Maximum [Member]
Exercise price per share, balance (in dollars per share)		0.83	1
Balance (in dollars per share)		0.39
Exercise price per share, granted (in dollars per share)		0.27	0.23
Exercise price per share, Expired (in dollars per share)		0.40
Exercise price per share, balance (in dollars per share)			0.83
Balance (in dollars per share)		0.39	$ 0.39
Exercise price per share, Vested (in dollars per share)		$ 0.83
[1]Aggregate intrinsic value based on closing common stock price of $0.20 at December 31, 2022.

Note 6 - Warrants (Details Text

Note 6 - Warrants (Details Textual) - USD ($)	1 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2022	Mar. 01, 2021
Share Price (in dollars per share)		$ 0.20	$ 0.20
Stock Issued During Period, Shares, Warrants Exercised (in shares)		1,283,333
Proceeds from Issuance of Warrants		$ 164,000
Note Payable, Maturing March 8, 2023 [Member]
Debt Instrument, Face Amount	$ 50,000			$ 50,000
Debt Instrument, Term (Year)	2 years
Six-month Warrants in Connection With the 2020 Unit Offering [Member]
Warrants and Rights Outstanding, Term (Year)			6 months
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)		5,435,996	13,568,524
Six-month Warrants in Connection With the 2020 Unit Offering [Member] | Minimum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 0.14	$ 0.19
Six-month Warrants in Connection With the 2020 Unit Offering [Member] | Maximum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 0.23	$ 0.26
Five-year Warrants in Connection With the 2020 Unit Offering [Member]
Warrants and Rights Outstanding, Term (Year)		5 years	5 years
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)		5,435,996	13,568,524
Five-year Warrants in Connection With the 2020 Unit Offering [Member] | Minimum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 0.16	$ 0.24
Five-year Warrants in Connection With the 2020 Unit Offering [Member] | Maximum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 0.29	$ 0.33
Warrants Issued in Connection with Conversion of Interest on Note Payable Maturing March 8, 2023 [Member]
Warrants and Rights Outstanding, Term (Year)	5 years
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)	225,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.16
Warrants and Rights Outstanding	$ 35,000

Note 6 - Warrants - Warrants Ou

Note 6 - Warrants - Warrants Outstanding (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Balance, outstanding (in shares)	36,765,562	32,980,989
Granted (in shares)	27,137,048	11,096,992
Exercised (in shares)	0	(1,283,333)
Exercised, price range (in dollars per share)
Expired (in shares)	(14,879,152)	(6,029,086)
Exercised (in shares)	0	1,283,333
Balance, outstanding (in shares)	49,023,398	36,765,562
Balance, aggregate intrinsic value	$ 691,000
Minimum [Member]
Balance, outstanding, price range (in dollars per share)	$ 0.13	$ 0.13
Granted, price range (in dollars per share)	0.12	0.12
Exercised, price range (in dollars per share)		0.12
Expired, price range (in dollars per share)	0.12	0.12
Balance, outstanding, price range (in dollars per share)	0.13	0.13
Maximum [Member]
Balance, outstanding, price range (in dollars per share)	1	1
Granted, price range (in dollars per share)	0.14	0.14
Exercised, price range (in dollars per share)		0.14
Expired, price range (in dollars per share)	0.48	0.70
Balance, outstanding, price range (in dollars per share)	1	1
Weighted Average [Member]
Balance, outstanding, price range (in dollars per share)	0.27	0.29
Granted, price range (in dollars per share)	0.23	0.21
Exercised, price range (in dollars per share)		0.13
Expired, price range (in dollars per share)	0.24	0.30
Balance, outstanding, price range (in dollars per share)	$ 0.26	$ 0.27

Note 6 - Warrants - Assumptions

Note 6 - Warrants - Assumptions Used to Determine Fair Value of Warrants (Details)	Dec. 31, 2022	Dec. 31, 2021
Measurement Input, Risk Free Interest Rate [Member]
Risk free interest rate		0.0071
Measurement Input, Price Volatility [Member]
Risk free interest rate	0.40	1
Measurement Input, Expected Term [Member]
Risk free interest rate	3
Minimum [Member] | Measurement Input, Risk Free Interest Rate [Member]
Risk free interest rate	0.0369
Minimum [Member] | Measurement Input, Expected Term [Member]
Risk free interest rate		5
Maximum [Member] | Measurement Input, Risk Free Interest Rate [Member]
Risk free interest rate	0.0388
Maximum [Member] | Measurement Input, Expected Term [Member]
Risk free interest rate		5

Note 7 - Accounts Payable and_3

Note 7 - Accounts Payable and Accrued Expenses - Summary of Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Accounts payable	$ 717	$ 350
Accrued payroll	198	184
Accrued interest	25	25
Total	940	559
Corporate, Non-Segment [Member]
Accounts payable	187	156
Accrued payroll	20	37
Accrued interest	25	25
Total
Operating Segments [Member] | Odor-No-More [Member]
Accounts payable	486	72
Accrued payroll	58	53
Accrued interest	0	0
Total
Operating Segments [Member] | BLEST [Member]
Accounts payable	7	73
Accrued payroll	120	94
Accrued interest	0	0
Total
Operating Segments [Member] | BioLargo Water [Member]
Accounts payable	119	96
Accrued payroll	0	0
Accrued interest	0	0
Total
Consolidation, Eliminations [Member]
Accounts payable	(82)	(47)
Accrued payroll	0	0
Accrued interest	0	0
Total

Note 8 - Provision for Income_2

Note 8 - Provision for Income Taxes (Details Textual)	12 Months Ended
	Dec. 31, 2022 USD ($)
Net Operating Loss Carryforward Expiration Term (Year)	20 years
Valuation Allowance Percentage	100%
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	$ 101,000,000
State and Local Jurisdiction [Member] | California Franchise Tax Board [Member]
Operating Loss Carryforwards, Total	$ 54,000,000

Note 9 - In-process Research _3

Note 9 - In-process Research and Development; Impairment Expense (Details Textual) - USD ($)					12 Months Ended
	Mar. 03, 2022	Dec. 31, 2020	Sep. 26, 2018	Dec. 30, 2015	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets, Net, Ending Balance						$ 3,023,000
Stock Issued During Period, Value, Issued for Services					$ 291,000	367,000
Asset Impairment Charges, Total					197,000	342,000
In Process Research and Development [Member]
Finite-Lived Intangible Assets, Net, Ending Balance	$ 2,150,000
Clyra Medical [Member]
Revenues, Total							$ 200,000
Clyra Medical [Member] | Beach House Consulting, LLC [Member]
Consulting Services, Monthly Payment				$ 23,000
Consulting Services, Period of Services (Year)				4 years
Stock Issued During Period, Shares, Issued for Services (in shares)				3,639
Stock Issued During Period, Value, Issued for Services				$ 788,000
Consulting Services, Three Consecutive Month Average Revenue Threshold for Consulting Fees to Accrue				$ 250,000
Asset Impairment Charges, Total					$ 197,000	197,000
Scion Acquisition [Member] | Clyra Medical [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)			21,000
Business Combination, Common Stock Accepted (in shares)	2,000,000
Debt Instrument, Decrease, Forgiveness	$ 305,000
Treasury Stock, Common, Shares (in shares)	5,142,858
Scion Acquisition [Member] | Clyra Medical [Member] | Noncompete Agreements [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Scion Acquisition [Member] | Clyra Medical [Member] | Promissory Note [Member]
Business Combination, Consideration Transferred, Liabilities Incurred			$ 1,250,000
Debt Instrument, Interest Rate, Stated Percentage			5%
Repayments of Long-Term Debt, Total						$ 243,000
Debt Instrument, Decrease, Forgiveness, Principal Outstanding	$ 1,007,000
Debt Instrument, Decrease, Forgiveness, Interest	$ 133,000
Scion Acquisition [Member] | Clyra Medical [Member] | Clyra Acquisition, Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)			10,000
Scion Acquisition [Member] | Clyra Medical [Member] | Clyra Acquisition, Common Stock Redeemable for BioLargo Common Shares [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)			7,142,858				6,200
Business Combination, Shares Acquired (in shares)			12,755
Stock Redeemed Upon Vesting of 10,000 Clyra Acquisition Shares, Shares (in shares)			10,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable		$ 2,150,000
Common Stock, Redeemable, Issuer Option, Shares (in shares)							2,200
Common Stock, Shares Issued upon Redemption (in shares)		1,428,571					1,428,571
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Earned (in shares)	5,000,000
Scion Acquisition [Member] | Clyra Medical [Member] | Clyra Acquisition, Newly Vested Common Stock for BioLargo Common Shares [Member]
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable							$ 257,000

Note 9 - In-process Research _4

Note 9 - In-process Research and Development; Impairment Expense - Summary of Impairment Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Asset Impairment Charges, Total	$ 197,000	$ 342,000
Impairment expense	$ (197,000)	(342,000)
Corporate Segment [Member]
Asset Impairment Charges, Total		2,150,000
Impairment expense		(2,150,000)
Clyra Medical [Member]
Asset Impairment Charges, Total		1,808,000
Impairment expense		(1,808,000)
In Process Research and Development [Member]
Asset Impairment Charges, Total		(2,150,000)
Impairment expense		2,150,000
In Process Research and Development [Member] | Corporate Segment [Member]
Asset Impairment Charges, Total		(2,150,000)
Impairment expense		2,150,000
In Process Research and Development [Member] | Clyra Medical [Member]
Asset Impairment Charges, Total		0
Impairment expense		0
Debt Obligations [Member]
Asset Impairment Charges, Total		1,007,000
Impairment expense		(1,007,000)
Debt Obligations [Member] | Corporate Segment [Member]
Asset Impairment Charges, Total		0
Impairment expense		0
Debt Obligations [Member] | Clyra Medical [Member]
Asset Impairment Charges, Total		1,007,000
Impairment expense		(1,007,000)
Accounts Payable and Accrued Interest [Member]
Asset Impairment Charges, Total		458,000
Impairment expense		(458,000)
Accounts Payable and Accrued Interest [Member] | Corporate Segment [Member]
Asset Impairment Charges, Total		0
Impairment expense		0
Accounts Payable and Accrued Interest [Member] | Clyra Medical [Member]
Asset Impairment Charges, Total		458,000
Impairment expense		(458,000)
Liability to Scion Shareholders [Member]
Asset Impairment Charges, Total		540,000
Impairment expense		(540,000)
Liability to Scion Shareholders [Member] | Corporate Segment [Member]
Asset Impairment Charges, Total		0
Impairment expense		0
Liability to Scion Shareholders [Member] | Clyra Medical [Member]
Asset Impairment Charges, Total		540,000
Impairment expense		(540,000)
Other Asset, Prepaid Marketing [Member]
Asset Impairment Charges, Total		197,000
Impairment expense		(197,000)
Other Asset, Prepaid Marketing [Member] | Corporate Segment [Member]
Asset Impairment Charges, Total		0
Impairment expense		0
Other Asset, Prepaid Marketing [Member] | Clyra Medical [Member]
Asset Impairment Charges, Total		197,000
Impairment expense		$ (197,000)

Note 10 - Noncontrolling Inte_3

Note 10 - Noncontrolling Interest - Clyra Medical (Details Textual) - USD ($)				9 Months Ended	12 Months Ended
	Dec. 20, 2022	Mar. 02, 2022	Jun. 30, 2020	Sep. 30, 2021	Dec. 31, 2022	Dec. 31, 2021	Apr. 08, 2022	Dec. 31, 2020
Stock Issued During Period, Value, Commitment Fee					$ 0
Preferred Stock, Shares Outstanding, Ending Balance (in shares)					0	0
Stock Issued During Period, Value, New Issues					$ 3,617,000	$ 4,882,000
Proceeds from Issuance of Preferred Stock and Preference Stock					$ 225,000	$ 0
Clyra Medical [Member]
Common Stock, Shares, Outstanding, Ending Balance (in shares)					91,149
Stock Issued During Period, Shares, New Issues (in shares)						161
Stock Issued During Period, Value, New Issues						$ 50,000
Shares Issued, Price Per Share (in dollars per share)	$ 310				$ 310	$ 310
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)					15,833	14,004		11,411
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)					$ 40.24	$ 1
Clyra Medical [Member] | Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Expense					$ 408,000	$ 564,000
Clyra Medical [Member] | Employees and Consultants [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)					1,829	2,594
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)					10 years
Clyra Medical [Member] | Employees and Consultants [Member] | Options With the Exercise Price of 1 Dollar [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)					1,597
Clyra Medical [Member] | Employees and Consultants [Member] | The Remaining Options [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)					$ 310
Clyra Medical [Member] | Employees and Consultants [Member] | Share-Based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Discount Rate					30%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum					2.32%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate					40%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)					10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum					3.83%
Clyra Medical [Member] | Vendors and Employees [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)						$ 1
Clyra Medical [Member] | Vendors and Employees [Member] | Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Expense				$ 564,000	$ 408,000
Clyra Medical [Member] | Warrants Issued in Conjunction With the Sale of Series A Preferred Stock [Member]
Warrants and Rights Outstanding, Term (Year)	3 years
Warrants and Rights Outstanding	$ 55,000
Clyra Medical [Member] | Shares Issued for Debt Owed to Biolargo [Member]
Debt Conversion, Converted Instrument, Amount		$ 633,091
Debt Conversion, Converted Instrument, Shares Issued (in shares)		2,032
Clyra Medical [Member] | Series A Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares)					2,075
Stock Issued During Period, Shares, New Issues (in shares)	725
Shares Issued, Price Per Share (in dollars per share)	$ 372
Proceeds from Issuance of Preferred Stock and Preference Stock	$ 225,000
Preferred Stock, Dividend Rate, Percentage	15%
Clyra Medical [Member] | Revolving Credit Facility [Member] | Vernal Bay Capital Group, LLC [Member] | Inventory Line of Credit [Member]
Debt Instrument, Interest Rate, Stated Percentage			15%
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,000,000
Proceeds from Lines of Credit, Total			260,000
Repayments of Lines of Credit			$ 99,000
Line of Credit Facility, Covenant, Additional Draws, Maximum Percentage of Total Principal Outstanding Allowed			50%
Line of Credit Facility, Covenant, Additional Draws, Minimum Amount Allowed			$ 200,000
Debt Instrument, Term (Year)			1 year
Line of Credit Facility, Monthly Percentage of Gross Product Sales Required to be Used as Payment of Debt on First 180 Days			30%
Line of Credit Facility, Monthly Percentage of Gross Product Sales Required to be Used as Payment of Debt after the First 180 Days			60%
Stock Issued During Period, Shares, Commitment Fee (in shares)			322		322
Stock Issued During Period, Value, Commitment Fee			$ 70,000
Debt Instrument, Percentage of Principal Payment, Cap					15%
Long-term Line of Credit, Total					$ 161,000	$ 187,000
Clyra Medical [Member] | Notes Payable, Other Payables [Member]
Debt Instrument, Face Amount							$ 100,000
Debt Instrument, Interest Rate, Stated Percentage							8%
Debt Instrument, Convertible, Sale of Stock Amount							$ 5,000,000
Debt Instrument, Convertible, Conversion Percentage							70%
Clyra Medical Technologies [Member]
Noncontrolling Interest, Ownership Percentage by Parent					58%
Clyra Medical [Member] | Common Stock [Member]
Investment Owned, Balance, Shares (in shares)					52,601
Clyra Medical [Member] | Preferred Stock, Series A [Member]
Investment Owned, Balance, Shares (in shares)					1,349

Note 10 - Noncontrolling Inte_4

Note 10 - Noncontrolling Interest - Clyra Medical - Common Shares Outstanding (Details) - Clyra Medical [Member] - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Options outstanding, balance (in shares)	14,004	11,411
Balance (in dollars per share)	$ 1	$ 1
Options granted (in shares)	1,829	2,594
Granted (in dollars per share)	$ 40.24	$ 1
Options outstanding, balance (in shares)	15,833	14,004
Balance (in dollars per share)	$ 5.53	$ 1
Maximum [Member]
Balance, Exercise Price Range (in shares)	1	1
Granted, Exercise Price (in dollars per share)	$ 310	$ 1
Balance, Exercise Price Range (in shares)	310	1
Minimum [Member]
Granted, Exercise Price (in dollars per share)	$ 1
Balance, Exercise Price Range (in shares)	1

Note 10 - Noncontrolling Inte_5

Note 10 - Noncontrolling Interest - Clyra Medical - Summary of Accounts Payable and Accrued Expenses (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Accounts payable	$ 717,000	$ 350,000
Accrued payroll	198,000	184,000
Accrued interest	25,000	25,000
Accounts payable and accrued expenses, total	940,000	559,000
Clyra Medical [Member]
Accounts payable	186	149
Accrued payroll	45	30
Accrued interest	7	51
Accounts payable and accrued expenses, total	$ 238	$ 230

Note 11 - BioLargo Engineerin_2

Note 11 - BioLargo Engineering, Science and Technologies, LLC (Details Textual) - USD ($)		1 Months Ended		12 Months Ended		25 Months Ended
	Nov. 04, 2019	Jan. 30, 2021	Sep. 30, 2017	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2019
Share-based Payment Arrangement, Noncash Expense, Total				$ 2,071,000	$ 1,872,000
Percentage of Profits Interests Vested	2.50%	3.75%
Percentage of Option to Purchase Shares of Common Stock	10%	15%
Seven Employees Working at BioLargo Engineering, Science & Technologies, LLC [Member]
Deferred Compensation Arrangement with Individual, Requisite Service Period (Year)			5 years
Potential Ownership Percentage of Subsidiary Held by Subsidiary Employees Based on Performance			30%
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	175,000	262,500		1,242,500	525,000
Incentive Issuance Stipulations for Subsidiary Employees, Accounts Receivable Collected by Year One of Operation			90%
Incentive Issuance Stipulations for Subsidiary Employees, Profit Earned in Year One of Operation			10%
Percentage of Profits Interests Vested				17.75%	11.25%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 44,000	$ 65,000		$ 135,000	$ 65,000
Seven Employees Working at BioLargo Engineering, Science & Technologies, LLC [Member] | Non-Qualified Stock Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)			1,750,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)			5 years
Share-based Payment Arrangement, Noncash Expense, Total						$ 0
BioLargo Engineering, Science & Technologies, LLC [Member]
Noncontrolling Interest, Ownership Percentage by Parent			100%	82%

Note 12 - Business Segment In_3

Note 12 - Business Segment Information (Details Textual)	12 Months Ended
	Dec. 31, 2022
Number of Operating Segments	4

Note 12 - Business Segment In_4

Note 12 - Business Segment Information - Segment Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Jan. 19, 2019
Revenue from Contract with Customer, Including Assessed Tax	$ 5,884,000	$ 2,531,000
Research and development	(1,319,000)	(1,367,000)
Operating loss	(5,390,000)	(6,778,000)
Interest expense	(53,000)	(234,000)
Net loss	(5,132,000)	(6,894,000)
Net loss	5,132,000	6,894,000
Tangible assets	3,958,000	2,522,000
Operating Lease, Right-of-Use Asset	867,000	453,000	$ 399,000
Investment in South Korean joint venture	33,000	48,000
Total	4,858,000
Finite-Lived Intangible Assets, Net, Ending Balance		3,023,000
Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	33,000	48,000
Corporate, Non-Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	5,000	7,000
Research and development	(674,000)	(1,001,000)
Operating loss	(3,971,000)	(5,688,000)
Interest expense	(24,000)	(118,000)
Net loss	(3,995,000)	(5,781,000)
Net loss	3,995,000	5,781,000
Tangible assets	669,000	555,000
Operating Lease, Right-of-Use Asset	136,000	222,000
Total	838,000
Finite-Lived Intangible Assets, Net, Ending Balance		825,000
Corporate, Non-Segment [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	33,000	48,000
Operating Segments [Member] | Odor-No-More [Member]
Revenue from Contract with Customer, Including Assessed Tax	4,374,000	1,419,000
Operating loss	1,130,000	(511,000)
Net loss	(1,304,000)	511,000
Net loss	1,304,000	(511,000)
Tangible assets	2,064,000	451,000
Operating Lease, Right-of-Use Asset	0	0
Total	2,064,000
Finite-Lived Intangible Assets, Net, Ending Balance		451,000
Operating Segments [Member] | Odor-No-More [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0	0
Operating Segments [Member] | Clyra Medical [Member]
Tangible assets	631,000	816,000
Operating Lease, Right-of-Use Asset	0	0
Total	631,000
Finite-Lived Intangible Assets, Net, Ending Balance		816,000
Operating Segments [Member] | Clyra Medical [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0	0
Operating Segments [Member] | BLEST [Member]
Tangible assets	441,000	595,000
Operating Lease, Right-of-Use Asset	731,000	231,000
Total	1,172,000
Finite-Lived Intangible Assets, Net, Ending Balance		433,000
Operating Segments [Member] | BLEST [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0	0
Operating Segments [Member] | BioLargo Water [Member]
Revenue from Contract with Customer, Including Assessed Tax	1,000	12,000
Research and development	(565,000)	(486,000)
Operating loss	(714,000)	(616,000)
Net loss	(604,000)	(566,000)
Net loss	604,000	566,000
Tangible assets	194,000	152,000
Operating Lease, Right-of-Use Asset	0	0
Total	194,000
Finite-Lived Intangible Assets, Net, Ending Balance		152,000
Operating Segments [Member] | BioLargo Water [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0	0
Operating Segments [Member] | BioLargo Engineering, Science & Technologies, LLC [Member]
Revenue from Contract with Customer, Including Assessed Tax	1,943,000	1,635,000
Research and development	(469,000)	(488,000)
Operating loss	(452,000)	(629,000)
Net loss	(425,000)	(629,000)
Net loss	425,000	629,000
Operating Segments [Member] | Clyra Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	56,000	139,000
Research and development	(110,000)	(66,000)
Operating loss	(1,383,000)	666,000
Interest expense	(29,000)	(116,000)
Net loss	(1,412,000)	593,000
Net loss	1,412,000	(593,000)
Consolidation, Eliminations [Member]
Revenue from Contract with Customer, Including Assessed Tax	(495,000)	(681,000)
Research and development	499,000	674,000
Tangible assets	(41,000)	(47,000)
Operating Lease, Right-of-Use Asset	0	0
Total	(41,000)
Finite-Lived Intangible Assets, Net, Ending Balance		(47,000)
Consolidation, Eliminations [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	$ 0	$ 0

Note 13 - Commitments and Con_3

Note 13 - Commitments and Contingencies (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2022	Jan. 19, 2019
Operating Lease, Expense	$ 316,000	$ 288,000
Operating Lease, Weighted Average Remaining Lease Term (Year)	9 years
Operating Lease, Right-of-Use Asset	$ 867,000	$ 453,000		$ 399,000
Lessee, Operating Lease, Discount Rate	18%
Lessee, Operating Lease, Liability, to be Paid, Total	$ 1,793,000
Operating Lease, Liability, Total	$ 870,000
Westminster, California Facility Lease [Member]
Lessee, Operating Lease, Renewal Term (Year)	4 years
Oak Ridge, Tennessee Facility Lease [Member]
Operating Lease, Weighted Average Remaining Lease Term (Year)			10 years
Operating Lease, Right-of-Use Asset			$ 443,000
Operating Lease, Liability, Total			$ 443,000

Note 13 - Commitments and Con_4

Note 13 - Commitments and Contingencies - Minimum Lease Payments (Details)	Dec. 31, 2022 USD ($)
December 31, 2023	$ 269,000
December 31, 2024	224,000
December 31, 2025	157,000
December 31, 2026	160,000
December 31, 2027	161,000
Thereafter	822,000
Total minimum lease payments	1,793,000
BioLargo/ONM Lease [Member]
December 31, 2023	118,000
December 31, 2024	70,000
Total minimum lease payments	188,000
BLEST Lease [Member]
December 31, 2023	151,000
December 31, 2024	154,000
December 31, 2025	157,000
December 31, 2026	160,000
December 31, 2027	161,000
Thereafter	822,000
Total minimum lease payments	$ 1,605,000

Note 14 - Subsequent Events (De

Note 14 - Subsequent Events (Details Textual) - USD ($)				3 Months Ended	11 Months Ended	12 Months Ended
	Mar. 21, 2023	Jan. 09, 2023	Dec. 20, 2022	Mar. 29, 2023	Dec. 13, 2022	Dec. 31, 2022	Dec. 31, 2021	Mar. 06, 2023	Jan. 01, 2023	Mar. 31, 2021	Mar. 01, 2021
Proceeds from Issuance of Common Stock						$ 3,617,000	$ 4,882,000
Share Price (in dollars per share)						$ 0.20	$ 0.20
Note Payable, Maturing March 8, 2023 [Member]
Debt Instrument, Face Amount										$ 50,000	$ 50,000
Warrants Issued with 2020 Unit Offering [Member] | Minimum [Member]
Warrants and Rights Outstanding, Term (Year)						6 months	6 months
Warrants Issued with 2020 Unit Offering [Member] | Maximum [Member]
Warrants and Rights Outstanding, Term (Year)						5 years	5 years
Clyra Medical [Member]
Stock Issued During Period, Shares, New Issues (in shares)							161
Shares Issued, Price Per Share (in dollars per share)			$ 310			$ 310	$ 310
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)						1,829	2,594
Series A Preferred Stock [Member] | Clyra Medical [Member]
Stock Issued During Period, Shares, New Issues (in shares)			725
Shares Issued, Price Per Share (in dollars per share)			$ 372
Lincoln Park Capital Fund, LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares)					6,011,701	6,011,701	24,255,920
Proceeds from Issuance of Common Stock					$ 1,253,000	$ 1,253,000	$ 4,018,000
Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues (in shares)				3,500,000
Common Stock, Share Subscribed but Unissued, Subscriptions Receivable				$ 694,640
Subsequent Event [Member] | Conversion of Clyra Medical Stock Into Biolargo Common Stock [Member]
Conversion of Stock, Shares Converted (in shares)		322
Conversion of Stock, Shares Issued (in shares)		527,983
Conversion of Stock, Conversion Price (in dollars per share)		$ 0.1894
Subsequent Event [Member] | Chief Financial Officer [Member]
Engagement Extension, Term (Year)	1 year
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Per Month (in shares)	25,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	300,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares (in shares)	25,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Expected to Vest, Monthly, Number of Shares (in shares)	25,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 0.20
Subsequent Event [Member] | Chief Financial Officer [Member] | Share-Based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Subsequent Event [Member] | BioLargo Energy Technologies, Inc (BETI) [Member]
Noncontrolling Interest, Ownership Percentage by Parent				96.80%
Subsequent Event [Member] | BioLargo Energy Technologies, Inc (BETI) [Member]
Stock Issued During Period, Shares, New Issues (in shares)				350,000
Share Price (in dollars per share)									$ 2
Proceeds from Issuance or Sale of Equity, Total				$ 700,000
Subsequent Event [Member] | Warrants Expiring Six Month After Investment Date [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)				3,500,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 0.228
Subsequent Event [Member] | Warrants Expiring Six Month After Investment Date [Member] | Minimum [Member]
Warrants and Rights Outstanding, Term (Year)				6 months
Subsequent Event [Member] | Warrants Issued with 2020 Unit Offering [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 0.285
Subsequent Event [Member] | Warrants Issued with 2020 Unit Offering [Member] | Maximum [Member]
Warrants and Rights Outstanding, Term (Year)				5 years
Subsequent Event [Member] | Warrants Expiring Five Years After Investment Date [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,787,579
Subsequent Event [Member] | Warrants Issued to Holder of a 50,000 Note [Member]
Warrants and Rights Outstanding, Term (Year)								5 years
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)								$ 0.21
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)								200,000
Subsequent Event [Member] | Clyra Medical [Member] | Warrant [Member]
Shares Issued, Price Per Share (in dollars per share)				$ 372
Warrants and Rights Outstanding, Term (Year)				3 years
Subsequent Event [Member] | Biolargo [Member] | BioLargo Energy Technologies, Inc (BETI) [Member]
Proceeds from Issuance or Sale of Equity, Total				$ 100,000
Subsequent Event [Member] | Series A Preferred Stock [Member] | Clyra Medical [Member]
Stock Issued During Period, Shares, New Issues (in shares)				726
Preferred Stock, Shares Subscribed but Unissued, Subscriptions Receivable				$ 225,000
Shares Issued, Price Per Share (in dollars per share)				$ 310
Subsequent Event [Member] | Lincoln Park Capital Fund, LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares)				545,402
Proceeds from Issuance of Common Stock				$ 105,000