BioLargo (BLGO) 10-Q 16 Aug 21 2021 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Aug. 10, 2021
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	Q2
Document Fiscal Year Focus	2021
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		228,147,577

Consolidated Balance Sheets (Cu

Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 1,357,000	$ 716,000
Accounts receivable, net of allowance	343,000	484,000
Inventories, net of allowance	262,000	277,000
Prepaid expenses and other current assets	90,000	28,000
Total current assets	2,052,000	1,505,000
Non-current assets
In-process research and development (Note 8)	2,150,000	2,150,000
Equipment, net of depreciation	69,000	60,000
Other non-current assets	35,000	35,000
Investment in South Korean joint venture	40,000	63,000
Right of use operating lease, net of amortization	311,000	341,000
Clyra Medical prepaid marketing (Note 9)	788,000	788,000
Total non-current assets	3,393,000	3,437,000
Total assets	5,445,000	4,942,000
Current liabilities:
Deferred revenue	139,000	48,000
Customer deposits	81,000	0
Lease liability	114,000	114,000
Total current liabilities	2,432,000	3,544,000
Long-term liabilities:
Long-term debt, noncurrent	485,000	507,000
Lease liability	196,000	226,000
Common stock held for redemption (Note 9)	900,000	900,000
Total long-term liabilities	1,781,000	1,633,000
Total liabilities	4,213,000	5,177,000
COMMITMENTS AND CONTINGENCIES (Note 12)
STOCKHOLDERS’ EQUITY (DEFICIT):
Preferred Series A, $0.00067 Par Value, 50,000,000 Shares Authorized, -0- Shares Issued and Outstanding, at June 30, 2021 and December 31, 2020	0	0
Common stock, $0.00067 Par Value, 400,000,000 Shares Authorized, 250,996,373 and 225,885,682 Shares Issued, at June 30, 2021 and December 31, 2020	168,000	151,000
Additional paid-in capital	140,292,000	135,849,000
Accumulated other comprehensive loss	(103,000)	(101,000)
Accumulated deficit	(135,294,000)	(132,041,000)
Total BioLargo Inc. and subsidiaries stockholders’ equity (deficit)	5,063,000	3,858,000
Non-controlling interest (Notes 9 and 10)	(3,831,000)	(4,093,000)
Total stockholders’ equity (deficit)	1,232,000	(235,000)
Total liabilities and stockholders’ equity (deficit)	5,445,000	4,942,000
Entities, Excluding Partially Owned Subsidiary [Member]
Current liabilities:
Accounts payable and accrued expenses	331,000	513,000
Debt obligations, net of discount and amortization (Note 4)	0	1,102,000
Accounts payable and accrued expenses	331,000	513,000
Long-term liabilities:
Long-term debt, noncurrent	485,000	507,000
Partially Owned Subsidiary [Member]
Current liabilities:
Accounts payable and accrued expenses	760,000	536,000
Debt obligations, net of discount and amortization (Note 4)	1,007,000	1,231,000
Accounts payable and accrued expenses	760,000	536,000
Long-term liabilities:
Long-term debt, noncurrent	$ 200,000	$ 0

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Jun. 30, 2021	Dec. 31, 2020
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)	250,996,373	225,885,682

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues
Revenue	$ 464,000	$ 418,000	$ 1,035,000	$ 856,000
Cost of revenue
Gross profit	201,000	217,000	433,000	395,000
Selling, general and administrative expenses	1,547,000	1,872,000	3,310,000	3,417,000
Research and development	356,000	350,000	683,000	684,000
Operating loss	(1,702,000)	(2,005,000)	(3,560,000)	(3,706,000)
Other (expense) income:
Interest expense	(89,000)	(747,000)	(182,000)	(1,504,000)
Loss on debt extinguishment	0	0	0	(214,000)
PPP loan forgiveness	0	0	43,000	0
Tax credit	1,000	44,000	1,000	44,000
Grant income	0	7,000	30,000	64,000
Total other expense:	(88,000)	(696,000)	(108,000)	(1,610,000)
Net loss	(1,790,000)	(2,701,000)	(3,668,000)	(5,316,000)
Net loss attributable to noncontrolling interest	(168,000)	(275,000)	(415,000)	(617,000)
Net loss attributable to common shareholders	$ (1,622,000)	$ (2,426,000)	$ (3,253,000)	$ (4,699,000)
Net loss per share attributable to common shareholders:
Loss per share attributable to shareholders – basic and diluted (in dollars per share)	$ (0.01)	$ (0.01)	$ (0.02)	$ (0.03)
Weighted average number of common shares outstanding: (in shares)	243,731,011	181,567,199	238,759,632	175,220,216
Comprehensive loss:
Net loss	$ (1,790,000)	$ (2,701,000)	$ (3,668,000)	$ (5,316,000)
Foreign currency translation	0	22,000	(2,000)	22,000
Comprehensive loss	(1,790,000)	(2,679,000)	(3,670,000)	(5,294,000)
Comprehensive loss attributable to noncontrolling interest	(168,000)	(275,000)	(415,000)	(617,000)
Comprehensive loss attributable to common stockholders	(1,622,000)	(2,404,000)	(3,255,000)	(4,677,000)
Product [Member]
Revenues
Revenue	319,000	301,000	762,000	580,000
Cost of revenue
Cost of Goods and Services Sold	(160,000)	(109,000)	(397,000)	(237,000)
Service [Member]
Revenues
Revenue	145,000	117,000	273,000	276,000
Cost of revenue
Cost of Goods and Services Sold	$ (103,000)	$ (92,000)	$ (205,000)	$ (224,000)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity (Deficit) (Unaudited) - USD ($)	Clyra Medical Technology Inc [Member]Common Stock [Member]	Clyra Medical Technology Inc [Member]Additional Paid-in Capital [Member]	Clyra Medical Technology Inc [Member]Retained Earnings [Member]	Clyra Medical Technology Inc [Member]AOCI Attributable to Parent [Member]	Clyra Medical Technology Inc [Member]Noncontrolling Interest [Member]	Clyra Medical Technology Inc [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, 2019							166,256,024
Balance at Dec. 31, 2019							$ 111,000	$ 121,327,000	$ (123,492,000)	$ (99,000)	$ (27,000)	$ (2,180,000)
Sale of common stock for cash (in shares)							4,848,305
Sale of common stock for cash							$ 3,000	898,000	0	0	0	901,000
Issuance of common stock for service (in shares)							1,039,490
Issuance of common stock for service							$ 1,000	177,000	0	0	0	178,000
Stock option compensation expense	$ 0	$ 420,000	$ 0	$ 0	$ 0	$ 420,000	0	320,000	0	0	0	320,000
Clyra Medical securities offering	0	15,000	0	0	10,000	25,000
Net loss							$ 0	0	(2,274,000)	0	(342,000)	(2,616,000)
Conversion of notes (in shares)							3,387,649
Conversion of notes							$ 2,000	432,000	0	0	0	434,000
Issuance of common stock for interest (in shares)							19,278
Issuance of common stock for interest							$ 0	4,000	0	0	0	4,000
Balance (in shares) at Mar. 31, 2020							178,479,317
Balance at Mar. 31, 2020							$ 119,000	123,121,000	(125,866,000)	(99,000)	89,000	(2,636,000)
Common stock issued as a financing fee; deferred offering costs (in shares)							2,928,571
Common stock issued as a financing fee; deferred offering costs							$ 2,000	(124,000)	0	0	0	(122,000)
Deemed dividend for the change in accounting for derivative liability							0	100,000	(100,000)	0	0	0
Allocation of noncontrolling interest from Clyra Stock option issuance							$ 0	(448,000)	0	0	448,000	0
Balance (in shares) at Dec. 31, 2019							166,256,024
Balance at Dec. 31, 2019							$ 111,000	121,327,000	(123,492,000)	(99,000)	(27,000)	(2,180,000)
Net loss												(5,316,000)
Foreign currency translation												22,000
Foreign currency translation												22,000
Balance (in shares) at Jun. 30, 2020							190,703,381
Balance at Jun. 30, 2020							$ 128,000	130,875,000	(128,292,000)	(77,000)	(4,239,000)	(1,605,000)
Balance (in shares) at Mar. 31, 2020							178,479,317
Balance at Mar. 31, 2020							$ 119,000	123,121,000	(125,866,000)	(99,000)	89,000	(2,636,000)
Sale of common stock for cash (in shares)							3,689,246
Sale of common stock for cash							$ 2,000	558,000	0	0	0	560,000
Issuance of common stock for service (in shares)							1,774,033
Issuance of common stock for service							$ 1,000	271,000	0	0	0	272,000
Stock option compensation expense	0	20,000	0	0	0	20,000	0	528,000	0	0	0	528,000
Noncontrolling interest allocation							0	4,401,000	0	0	(4,401,000)	0
Clyra Medical securities offering	0	476,000	0	0	348,000	824,000
Net loss							0	0	(2,426,000)	0	(275,000)	(2,701,000)
Foreign currency translation							$ 0	0	0	22,000	0	22,000
Conversion of notes (in shares)							6,463,784
Conversion of notes							$ 6,000	682,000	0	0	0	688,000
Issuance of common stock for interest (in shares)							297,001
Issuance of common stock for interest							$ 0	30,000	0	0	0	30,000
Foreign currency translation							$ 0	0	0	22,000	0	22,000
Balance (in shares) at Jun. 30, 2020							190,703,381
Balance at Jun. 30, 2020							$ 128,000	130,875,000	(128,292,000)	(77,000)	(4,239,000)	(1,605,000)
Clyra Medical stock for other asset (See Note 2)							$ 0	788,000	0	0	0	788,000
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)
Sale of common stock for cash (in shares)							13,330,619
Sale of common stock for cash							$ 9,000	2,097,000	0	0	0	2,106,000
Issuance of common stock for service (in shares)							747,487
Issuance of common stock for service							$ 1,000	110,000	0	0	0	111,000
Stock option compensation expense	0	161,000	0	0	0	161,000	0	424,000	0	0	0	424,000
Warrants and conversion feature issued as discount on convertible note payable							0	35,000	0	0	0	35,000
Noncontrolling interest allocation							0	(313,000)	0	0	313,000	0
Clyra Medical securities offering	0	0	0	0	50,000	50,000
Net loss							0	0	(1,631,000)	0	(247,000)	(1,878,000)
Foreign currency translation							0	0	0	(2,000)	0	(2,000)
Foreign currency translation							$ 0	0	0	(2,000)	0	(2,000)
Balance (in shares) at Mar. 31, 2021							239,963,788
Balance at Mar. 31, 2021							$ 161,000	138,363,000	(133,672,000)	(103,000)	(3,977,000)	772,000
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)
Net loss												(3,668,000)
Foreign currency translation												(2,000)
Foreign currency translation												(2,000)
Balance (in shares) at Jun. 30, 2021							250,996,373
Balance at Jun. 30, 2021							$ 168,000	140,292,000	(135,294,000)	(103,000)	(3,831,000)	1,232,000
Balance (in shares) at Mar. 31, 2021							239,963,788
Balance at Mar. 31, 2021							$ 161,000	138,363,000	(133,672,000)	(103,000)	(3,977,000)	772,000
Sale of common stock for cash (in shares)							8,627,237
Sale of common stock for cash							$ 6,000	1,408,000	0	0	0	1,414,000
Issuance of common stock for service (in shares)							357,132
Issuance of common stock for service							$ 0	60,000	0	0	0	60,000
Stock option compensation expense	$ 0	$ 102,000	$ 0	$ 0	$ 0	$ 102,000	0	330,000	0	0	0	330,000
Noncontrolling interest allocation							0	(314,000)	0	0	314,000	0
Net loss							0	0	(1,622,000)	0	(168,000)	(1,790,000)
Foreign currency translation							$ 0	0	0	0	0	0
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 interest (in shares)							81,777
Issuance of common stock for interest							$ 0	16,000	0	0	0	16,000
Foreign currency translation							$ 0	0	0	0	0	0
Balance (in shares) at Jun. 30, 2021							250,996,373
Balance at Jun. 30, 2021							$ 168,000	$ 140,292,000	$ (135,294,000)	$ (103,000)	$ (3,831,000)	$ 1,232,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net loss	$ (3,668,000)	$ (5,316,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock option compensation expense	1,017,000	1,074,000
Common stock issued in lieu of salary to officers and fees for services from vendors	171,000	450,000
Common stock issued for interest	16,000	34,000
Interest expense related to amortization of the discount on convertible notes payable and line of credit	110,000	1,327,000
PPP loan forgiveness	(43,000)	0
Loss on extinguishment of debt	0	214,000
Loss on investment in South Korean joint venture	23,000	15,000
Bad debt expense	0	11,000
Depreciation expense	12,000	33,000
Changes in assets and liabilities:
Accounts receivable	141,000	86,000
Prepaid expenses and other current assets	62,000	4,000
Inventories	15,000	(100,000)
Customer deposits	81,000	4,000
Deferred revenue	91,000	(22,000)
Net cash used in operating activities	(2,054,000)	(2,047,000)
Cash flows from investing activities
Investment in South Korean joint venture	0	(100,000)
Purchase and sale of equipment	(21,000)	16,000
Net cash used in investing activities	(21,000)	(84,000)
Cash flows from financing activities
Proceeds from sales of common stock	3,520,000	1,461,000
Proceeds from payroll protection program loan	0	349,000
Payment of debt obligations	(828,000)	0
Net cash provided by financing activities	2,718,000	2,661,000
Net effect of foreign currency translation	(2,000)	22,000
Net change in cash	641,000	552,000
Cash at beginning of period	716,000	655,000
Cash at end of period	1,357,000	1,207,000
Supplemental disclosures of cash flow information
Interest	33,000	50,000
Income taxes	0	2,000
Non-cash investing and financing activities
Fair value of warrants issued with convertible notes	35,000	0
Inventory included in accounts payable and accrued expense	0	55,000
Lincoln Park deferred offering costs, recorded as additional paid-in capital	0	(122,000)
Conversion of notes payable to common stock	328,000	1,122,000
Exchange of consulting services for Clyra common shares	0	788,000
Deemed dividend	0	100,000
Allocation of noncontrolling interest	627,000	4,849,000
Clyra Medical Common Stock [Member]
Cash flows from financing activities
Proceeds from sales of common stock	50,000	849,000
Entities, Excluding Partially Owned Subsidiary [Member]
Changes in assets and liabilities:
Accounts payable and accrued expenses	(182,000)	47,000
Partially Owned Subsidiary [Member]
Changes in assets and liabilities:
Accounts payable and accrued expenses	224,000	100,000
Cash flows from financing activities
Payment of Clyra Medical debt obligations	$ (24,000)	$ 0

Note 1 - Business and Organizat

Note 1 - Business and Organization	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Note 1. Description of Business BioLargo, Inc. is an innovative technology developer and environmental engineering company driven by a mission to “make life better” by delivering robust, sustainable solutions for a broad range of industries and applications, with a focus on clean water, clean air and a cleaner earth. The company also owns a minority interest in a medical products subsidiary that has licensed BioLargo’s technologies. 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 six June 30, 2021, June 30, 2021, not 2021 3. During the six June 30, 2021, 11. not 3 As of June 30, 2021, six June 30, 2021 4 9 Inventory Line of Credit June 30, 2021 June ( 9, Note Payable (Scion) June 2023. August 2021, March 2023. During the six June 30, 2021, 2020 3 If we are unable to rely on our current arrangement with Lincoln Park to fund our working capital requirements, we would have to rely on other forms of financing, and there is no To reduce our operational cash burdens, we regularly issue officers and vendors stock or options in lieu of cash compensation, and we anticipate that we will continue to be able to do so in the future. In the six June 30, 2021, 5, Chief Financial Officer Extension The foregoing factors raise substantial doubt about our ability to continue as a going concern. Ultimately, our ability to continue as a going concern is dependent upon our ability to attract significant new sources of capital, 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 BIOLARGO, INC. AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED) Organization We are a Delaware corporation formed in 1991. 2006; 2009; 2019, 2014; 2016. 2017 10 2012, 2, 9 The unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States of America for interim financial information and pursuant to Rule 8 03 X 1933, not six June 30, 2021 not may December 31, 2021, 10 December 31, 2020, March 30, 2021.

Note 2 - Summary of Significant

Note 2 - Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Significant Accounting Policies [Text Block]	Note 2. In the opinion of management, the accompanying balance sheet and related statements of operations, cash flows, and stockholders’ deficit include all adjustments, consisting only of normal recurring items, necessary for their fair presentation in conformity with accounting principles generally accepted in the United States of America. Principles of Consolidation The consolidated financial statements include the accounts of the Company, its wholly owned subsidiaries, BLEST, and Clyra Medical. Management believes Clyra Medical’s financial statements are appropriately consolidated with that of the Company after reviewing the Accounting Standards Codification (“ASC”), 810, 810 not 9. All intercompany accounts and transactions have been eliminated in the financial statement presentation. 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 June 30, 2021 December 31, 2020, June 30, 2021 December 31, 2020 BioLargo, Inc. and subsidiaries $ 1,338 $ 637 Clyra Medical Technologies, Inc. 19 79 Total $ 1,357 $ 716 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 June 30, 2021 December 31, 2020, Credit Concentration We have a limited number of customers that account for significant portions of our revenue. During the six June 30, 2021 2020, 10% June 30, 2021 June 30, 2020 Customer A 22 % <10 % Customer B 19 % <10 % Customer C 11 % <10 % Customer D <10 % 13 % We had three customers that each accounted for more than 10% June 30, 2021, December 31, 2020, June 30, 2021 December 31, 2020 Customer C 31 % <10 % Customer D 17 % <10 % Customer E 11 % <10 % Customer F <10 % 32 % Customer G <10 % 10 % 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 June 30, 2021, December 31, 2020, $3,000. June 30, 2021 December 31, 2020 Raw material $ 91 $ 111 Finished goods 171 166 Total $ 262 $ 277 Other Assets Other Assets consisted of security deposits of $35,000 related to our business offices. 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 three six June 30, 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 three six June 30, 2021 2020, 8 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 stock options and warrants were exercised into common stock. For the three six June 30, 2021 2020, 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, 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 six June 30, 2021 2020: 2021 2020 Non Plan 2018 Plan Non Plan 2018 Plan Risk free interest rate 1.73 % 0.93 – 1.73% 0.88 % 0.88 – 1.90% Expected volatility 124 % 123 – 124% 131 % 131 – 133% 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 Historically, we have not Warrants Warrants issued with our convertible promissory notes, note payables, line of credit 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. Further, the convertible debt instrument is examined for any intrinsic beneficial conversion feature (“BCF”) of which the conversion price is less than the closing common stock price on date of issuance. If the relative fair value method is used to value the convertible debt instrument and there is an intrinsic BCF, a further analysis is undertaken of the BCF using an effective conversion price which assumes the conversion price is the relative fair value divided by the number of shares the convertible debt is converted into by its terms. The BCF value is accounted for as equity. The warrant and BCF relative fair values are also recorded as a discount to the convertible promissory notes. At 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: Step 2: Step 3: Step 4: Step 5: Products sold a through a contract with the customer and 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 Canadian National Research Institute – Industrial Research Assistance Program (NRC-IRAP) and the National Science and Engineering Research Council of Canada (NSERC). The grants received are considered other income and are included in our consolidated statements of operations. We received our 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 June 30, 2021, December 31, 2020. The Company assessed its earnings history, trends and estimates of future earnings and determined that the deferred tax asset could not June 30, 2021. 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 (excluding debt and equity instruments) as of June 30, 2021 December 31, 2020, Tax Credits Our research and development activities in Canada may not Leases In accordance with ASC 842, No June 30, 2021, Recent Accounting Pronouncements In May 2021, No. 2021 04, In August 2020, No. 2020 06, 470 20 815 40 1 not not 2 December 15, 2021, December 15, 2023, not In January 2020, No 2020 01, 321 323 815 321, 323, 815”. 321 323 2016 01. 321 10 35 2, 321 not

Note 3 - Sale of Stock for Cash

Note 3 - Sale of Stock for Cash	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Stock Purchase Agreement [Text Block]	Note 3. Lincoln Park Financing On March 30, 2020, three may three 12 no first August 2017 1 April 10, 2020. April 21, 2020, April 29, 2020, August 2017. During the six June 30, 2021 2020, June 30, 2021, 13 2020 During the six June 30, 2021 2020, March 2020, six six five 6, Warrants Issued in 2020

Note 4 - Debt Obligations

Note 4 - Debt Obligations	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Debt Disclosure [Text Block]	Note 4. The following table summarizes our debt obligations outstanding as of June 30, 2021, December 31, 2020 ( not 9, Debt Obligations of Clyra Medical June 30, 2021 (Unaudited) December 31, 2020 Current portion of debt: Note payable, matures on demand 60 days’ notice (or March 8, 2023) $ — $ 50 Line of credit, matures on 30-day demand — 50 Total notes payable and line of credit $ — $ 100 Convertible notes payable: Convertible note payable, matures April 20, 2021 $ — $ 100 Convertible note payable, matures August 9, 2021 — 600 Convertible notes, mature August 12 and 16, 2021 — 406 Total convertible notes payable — 1,106 Debt discount, net of amortization — (104 ) Total current liabilities — 1,102 Long-term debt: Convertible note payable, matures March 1, 2023 $ 50 $ — Debt discount, net of amortization (29 ) — SBA Paycheck Protection Program loans 314 357 SBA EIDL Loan 150 150 Total long-term liabilities 485 507 Total $ 485 $ 1,609 For the six June 30, 2021 2020, The following discussion includes debt instruments to which amendments were made or included other activity that management deemed appropriate to disclose during the six June 30, 2021 2020. 10 March 30, 2021. Cash payment of debt obligations On May 17, 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 into shares of common stock On May 18, 2021, August 18, 2021, On its maturity date of April 20, 2021, Amendment to Note payable matures on 60 notice (or March 8, 2023) On March 1, 2021, March 1, 2023, 6

Note 5 - Share-based Compensati

Note 5 - Share-based Compensation	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	Note 5. Issuance of Common Stock in exchange for payment of payables Payment of Officer Salaries On March 31, 2021, On June 30, 2020, March 31, 2020, Payment of Consultant Fees On June 30, 2021, March 31, 2021, On June 30, 2020, March 31, 2020, Payment of Accrued Interest During the three June 30, 2021, On June 30, 2020, March 31, 2020, Stock Option Expense During the six June 30, 2021 2020, 2018 2007 9 2018 On June 22, 2018, 2018 “2018 may 2018 2018 January 1st Activity for our stock options under the 2018 six June 30, 2021 June 30, 2020, Weighted Average Aggregate Options Exercise Price per intrinsic Outstanding Price per share share Value (1) Balance, December 31, 2020 18,865,525 $0.16 – 0.40 $ 0.19 Granted 2,483,691 0.13 – 0.23 0.19 Expired — — — Balance, June 30, 2021 21,349,216 $0.12 – 0.43 $ 0.19 Non-vested (4,218,833 ) 0.12 – 0.40 0.23 Vested, June 30, 2021 17,130,383 $0.12 – 0.43 $ 0.18 $ 250,000 Balance, December 31, 2019 9,214,356 $0.16 – 0.43 $ 0.25 Granted 8,610,689 0.17 – 0.22 0.19 Expired (200,000 ) 0.18 – 0.34 0.26 Balance, June 30, 2020 17,625,045 $0.16 – 0.43 $ 0.20 ( 1 June 30, 2021. The options granted to purchase 2,483,691 shares during the six June 30, 2021 $130,000, four The options granted under the 2018 six June 30, 2020 one six June 30, 2020, January 31, 2021; ( $130,000; four $65,000; Chief Financial Officer Contract Extension On March 17, 2021, February 1, 2008 ( February 25, 2020 ( October 1, 2019, January 31, 2021 ( As compensation for the Extended Term, Mr. Dargan was issued an option (“Option”) to purchase 300,000 shares of our common stock. The Option vests over the period of the Extended Term, with 125,000 shares having vested as of June 30, 2021, January 31, 2022, March 17, 2021, ten 2018 twelve 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 2007 On September 7, 2007, April 29, 2011, 2007 “2007 may September 7, 2017. September 2017, Activity for our stock options under the 2007 six June 30, 2021 2020 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 (1,453,855 ) 0.39 - 0.51 0.40 Balance, June 30, 2021 4,235,508 $0.23 - 1.65 $ 0.45 $ — Balance, December 31, 2019 8,769,451 $0.23 – 0.94 $ 0.42 Expired (930,000 ) 0.39 – 0.58 0.56 Balance, June 30, 2020 7,839,451 $0.23 – 1.65 $ 0.41 ( 1 June 30, 2021. Non-Plan Options issued Activity of our non-plan stock options issued for the six June 30, 2021 2020 Weighted Non-plan average Aggregate Options Exercise price per Intrinsic outstanding price per share share value (1) Balance, December 31, 2020 20,749,583 $0.17 – 1.00 $ 0.41 Granted 43,956 0.23 0.23 Balance, June 30, 2021 20,793,539 $0.17 – 1.00 $ 0.41 Non-vested (1,996,576 ) 0.17 – 0.45 0.45 Vested, June 30, 2021 18,796,963 $0.17 – 1.00 $ 0.41 $ 28,000 Balance, December 31, 2019 19,604,107 $0.23 – 1.00 $ 0.41 Granted 292,437 0.17 – 0.21 0.18 Balance, June 30, 2020 19,896,544 $0.17 – 1.00 $ 0.41 ( 1 – Aggregate intrinsic value based on closing common stock price of $0.17 at June 30, 2021. During the six June 30, 2021, During the six June 30, 2020,

Note 6 - Warrants

Note 6 - Warrants	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Warrants [Text Block]	Note 6. We issued warrants to purchase our common stock, at various prices for the six June 30, 2021 2020, Weighted average Aggregate Warrants Exercise price per Intrinsic outstanding price per share share value (1) Balance, December 31, 2020 32,980,989 $0.16 – 1.00 $ 0.29 Issued 7,088,094 0.14 – 0.26 0.20 Expired (1,046,528 ) 0.19 – 0.35 0.24 Balance, June 30, 2021 39,022,555 $0.14 – 1.00 $ 0.27 $ 140,000 Balance, December 31, 2019 43,231,161 $0.16 – 1.00 $ 0.42 Issued 3,934,592 0.13 - 0.24 0.13 Expired (14,272,820 ) 0.40 - 0.49 0.30 Balance, June 30, 2020 32,892,933 $0.16 – 1.00 $ 0.35 ( 1 Aggregate intrinsic value based on closing common stock price of $0.17 at June 30, 2021 Warrants issued in 2020 During the six June 30, 2021, 2020 3 six five Warrant issued in conjunction with amendment to note payable On March 1, 2021, 4 five two 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: June 30, 2021 June 30, 2020 Risk free interest rate 0.71% 0.23% Expected volatility 100% 112 Expected dividend yield — — Forfeiture rate — — Expected life in years .5 – 5 0.33 – 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	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Accounts Payable and Accrued Liabilities Disclosure [Text Block]	Note 7. Accounts payable and accrued expenses for our operations other than our partially-owned subsidiary Clyra Medical included the following (in thousands): June 30, 2021 December 31, 2020 Accounts payable and accrued expense $ 145 $ 315 Accrued interest 25 42 Accrued payroll 161 156 Total accounts payable and accrued expenses $ 331 $ 513 Accounts payable and accrued expenses includes ordinary business payables incurred by the Company and its operational subsidiaries. See Note 9, Accounts Payable and Accrued Expenses

Note 8 - In-process Research an

Note 8 - In-process Research and Development	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
In Process Research and Development [Text Block]	Note 8. On September 26, 2018,

Note 9 - Noncontrolling Interes

Note 9 - Noncontrolling Interest - Clyra Medical	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Noncontrolling Interest Disclosure [Text Block]	Note 9. Clyra Medical As discussed in Note 2, June 30, 2021. Acquisition of In-process Research and Development On September 26, 2018, On December 17, 2018, $1 one one fifth June 30, 2021, Debt Obligations of Clyra Medical Note Payable (Scion) In conjunction with the transaction in which certain intellectual property was purchased from Scion, Clyra issued a promissory note to Scion in the principal amount of $1,250,000 on September 26, 2018 ( June 26th June 30, 2021 December 31, 2020, June 26, 2021, one June 26, 2022. Inventory Line of Credit On June 30, 2020, one Clyra is required to use funds from the line of credit to produce inventory. Additional draws are conditional upon Clyra presenting invoices or purchase orders to the lender equal to the greater of one one first 180 may During the six June 30, 2021, April, 2021, one June 30, 2022. August 31, 2021, September 2021, six As of June 30, 2021, Prepaid Marketing - Consulting Agreement On December 30, 2015, four June 30, 2020, three not Clyra Medical Equity transactions As of June 30, 2021, Shareholder Shares Percent BioLargo, Inc. 49,207 45 % Sanatio Capital 18,704 17 % Scion Solutions(1) 21,700 20 % Other 19,280 18 % Total 108,891 The above amounts do not not Sales of Common Shares During the six June 30, 2021 2020, Stock Options Clyra issues options to its employees and consultants in lieu of compensation owed on a regular basis. As of December 31, 2020, six June 30, 2021 2020, six June 30, 2021 2020 no Clyra Accounts Payable and Accrued Expenses Clyra had the following accounts payable and accrued expenses as follows: June 30, 2021 December 31, 2020 Accounts payable and accrued expense $ 582 $ 402 Accrued interest 127 32 Accrued payroll 51 102 Total Clyra Medical accounts payable and accrued expenses $ 760 $ 536

Note 10 - BioLargo Engineering,

Note 10 - BioLargo Engineering, Science and Technologies, LLC	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Wholly-Owned Subsidiary [Text Block]	Note 10. In September 2017, three six 11, Business Segment Information 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. June 30, 2021.

Note 11 - Business Segment Info

Note 11 - Business Segment Information	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Segment Reporting Disclosure [Text Block]	Note 11. BioLargo currently has four operating business segments, plus its corporate entity which is responsible for general corporate operations, including administrative functions, finance, human resources, marketing, legal, etc. The four 1. ONM Environmental (formerly Odor- No 2. Clyra Medical Technologies (“Clyra”) -- which develops and sells medical products based on our technologies, including Clyraguard Personal Protective Spray; 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, developing manufacturing operations for hand sanitizers and supporting the development of iodine based disinfecting products for the company (located in Edmonton, Alberta Canada). Historically, none third The segment information for the three six June 30, 2021 2020, Three months ended June 30, Six months ended June 30, 2021 2020 2021 2020 Revenue BioLargo corporate $ — $ — $ 7 $ — ONM 318 299 638 596 BLEST 266 160 654 444 Water — — 9 — Clyra Medical — 21 114 21 Intersegment revenue (120 ) (62 ) (387 ) (205 ) Total $ 464 $ 418 $ 1,035 $ 856 Operating loss BioLargo corporate $ (937 ) $ (1,129 ) $ (1,860 ) $ (1,936 ) ONM (107 ) (134 ) (283 ) (287 ) Clyra Medical (300 ) (422 ) (739 ) (728 ) BLEST (190 ) (124 ) (373 ) (331 ) Water (168 ) (196 ) (305 ) (424 ) Total $ (1,702 ) $ (2,005 ) $ (3,560 ) $ (3,706 ) Interest expense BioLargo corporate $ (51 ) $ (735 ) $ (106 ) $ (1,479 ) Clyra Medical (38 ) (12 ) (76 ) (25 ) Total $ (89 ) $ (747 ) $ (182 ) $ (1,504 ) Research and development expense BioLargo corporate $ (209 ) $ (119 ) $ (545 ) $ (321 ) Clyra Medical (6 ) (47 ) (33 ) (61 ) BLEST (123 ) (85 ) (228 ) (166 ) Water (138 ) (137 ) (257 ) (317 ) Intersegment R&D 120 38 380 181 Total $ (356 ) $ (350 ) $ (683 ) $ (684 ) The segment asset information for June 30, 2021 December 31, 2020, As June 30, 2021 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 1,072 $ 431 $ 1,016 $ 321 $ 151 $ (47 ) $ 2,944 Right of use 185 — — 126 — — 311 Investment in South Korean joint venture 40 — — — — — 40 Intangible assets 2,150 — — — — — 2,150 As of December 31, 2020 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 603 $ 624 $ 1,125 $ 314 $ 105 $ (42 ) $ 2,388 Right of use 215 — — 126 — — 341 Investment in South Korean joint venture 63 — — — — — 63 Intangible assets 2,150 — — — — — 2,150

Note 12 - Commitments and Conti

Note 12 - Commitments and Contingencies	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	Note 12. 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. For the six June 30, 2021 2020, June 30, 2021, three On January 1, 2019, 842 not not August 2016, August 2020, four 2020, four four four not one three September 2022, one five No five one None no not no

Note 13 - Subsequent Events

Note 13 - Subsequent Events	6 Months Ended
	Jun. 30, 2021
Notes to Financial Statements
Subsequent Events [Text Block]	Note 13. Management has evaluated subsequent events through the date of the filing of this Annual Report and management noted the following for disclosure. Sales to Lincoln Park From July 1, 2021, August 9, 2021, 884,391shares 3 Unit Offering Investment From July 1, 2021, August 12, 2021, one 2020 3 six five

Significant Accounting Policies

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2021
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, BLEST, and Clyra Medical. Management believes Clyra Medical’s financial statements are appropriately consolidated with that of the Company after reviewing the Accounting Standards Codification (“ASC”), 810, 810 not 9. All intercompany accounts and transactions have been eliminated in the financial statement presentation.
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 June 30, 2021 December 31, 2020, June 30, 2021 December 31, 2020 BioLargo, Inc. and subsidiaries $ 1,338 $ 637 Clyra Medical Technologies, Inc. 19 79 Total $ 1,357 $ 716
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 June 30, 2021 December 31, 2020,
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 six June 30, 2021 2020, 10% June 30, 2021 June 30, 2020 Customer A 22 % <10 % Customer B 19 % <10 % Customer C 11 % <10 % Customer D <10 % 13 % We had three customers that each accounted for more than 10% June 30, 2021, December 31, 2020, June 30, 2021 December 31, 2020 Customer C 31 % <10 % Customer D 17 % <10 % Customer E 11 % <10 % Customer F <10 % 32 % Customer G <10 % 10 %
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 June 30, 2021, December 31, 2020, $3,000. June 30, 2021 December 31, 2020 Raw material $ 91 $ 111 Finished goods 171 166 Total $ 262 $ 277
Other Assets, Policy [Policy Text Block]	Other Assets Other Assets consisted of security deposits of $35,000 related to our business offices.
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 three six June 30, 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 three six June 30, 2021 2020, 8
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 stock options and warrants were exercised into common stock. For the three six June 30, 2021 2020,
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, 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 six June 30, 2021 2020: 2021 2020 Non Plan 2018 Plan Non Plan 2018 Plan Risk free interest rate 1.73 % 0.93 – 1.73% 0.88 % 0.88 – 1.90% Expected volatility 124 % 123 – 124% 131 % 131 – 133% 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 Historically, we have not
Warrant Policy [Policy Text Block]	Warrants Warrants issued with our convertible promissory notes, note payables, line of credit 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. Further, the convertible debt instrument is examined for any intrinsic beneficial conversion feature (“BCF”) of which the conversion price is less than the closing common stock price on date of issuance. If the relative fair value method is used to value the convertible debt instrument and there is an intrinsic BCF, a further analysis is undertaken of the BCF using an effective conversion price which assumes the conversion price is the relative fair value divided by the number of shares the convertible debt is converted into by its terms. The BCF value is accounted for as equity. The warrant and BCF relative fair values are also recorded as a discount to the convertible promissory notes. At 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: Step 2: Step 3: Step 4: Step 5: Products sold a through a contract with the customer and 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 Canadian National Research Institute – Industrial Research Assistance Program (NRC-IRAP) and the National Science and Engineering Research Council of Canada (NSERC). The grants received are considered other income and are included in our consolidated statements of operations. We received our 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 June 30, 2021, December 31, 2020. The Company assessed its earnings history, trends and estimates of future earnings and determined that the deferred tax asset could not June 30, 2021. 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 (excluding debt and equity instruments) as of June 30, 2021 December 31, 2020,
Tax Credits [Policy Text Block]	Tax Credits Our research and development activities in Canada may not
Lessee, Leases [Policy Text Block]	Leases In accordance with ASC 842, No June 30, 2021,
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements In May 2021, No. 2021 04, In August 2020, No. 2020 06, 470 20 815 40 1 not not 2 December 15, 2021, December 15, 2023, not In January 2020, No 2020 01, 321 323 815 321, 323, 815”. 321 323 2016 01. 321 10 35 2, 321 not

Note 2 - Summary of Significa_2

Note 2 - Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2021
Notes Tables
Schedule of Cash and Cash Equivalents [Table Text Block]	June 30, 2021 December 31, 2020 BioLargo, Inc. and subsidiaries $ 1,338 $ 637 Clyra Medical Technologies, Inc. 19 79 Total $ 1,357 $ 716
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	June 30, 2021 June 30, 2020 Customer A 22 % <10 % Customer B 19 % <10 % Customer C 11 % <10 % Customer D <10 % 13 % June 30, 2021 December 31, 2020 Customer C 31 % <10 % Customer D 17 % <10 % Customer E 11 % <10 % Customer F <10 % 32 % Customer G <10 % 10 %
Schedule of Inventory, Current [Table Text Block]	June 30, 2021 December 31, 2020 Raw material $ 91 $ 111 Finished goods 171 166 Total $ 262 $ 277
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	2021 2020 Non Plan 2018 Plan Non Plan 2018 Plan Risk free interest rate 1.73 % 0.93 – 1.73% 0.88 % 0.88 – 1.90% Expected volatility 124 % 123 – 124% 131 % 131 – 133% Expected dividend yield — — — — Forfeiture rate — — — — Life in years 10 10 10 10

Note 4 - Debt Obligations (Tabl

Note 4 - Debt Obligations (Tables)	6 Months Ended
	Jun. 30, 2021
Notes Tables
Schedule of Debt [Table Text Block]	June 30, 2021 (Unaudited) December 31, 2020 Current portion of debt: Note payable, matures on demand 60 days’ notice (or March 8, 2023) $ — $ 50 Line of credit, matures on 30-day demand — 50 Total notes payable and line of credit $ — $ 100 Convertible notes payable: Convertible note payable, matures April 20, 2021 $ — $ 100 Convertible note payable, matures August 9, 2021 — 600 Convertible notes, mature August 12 and 16, 2021 — 406 Total convertible notes payable — 1,106 Debt discount, net of amortization — (104 ) Total current liabilities — 1,102 Long-term debt: Convertible note payable, matures March 1, 2023 $ 50 $ — Debt discount, net of amortization (29 ) — SBA Paycheck Protection Program loans 314 357 SBA EIDL Loan 150 150 Total long-term liabilities 485 507 Total $ 485 $ 1,609

Note 5 - Share-based Compensa_2

Note 5 - Share-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2021
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 $0.16 – 0.40 $ 0.19 Granted 2,483,691 0.13 – 0.23 0.19 Expired — — — Balance, June 30, 2021 21,349,216 $0.12 – 0.43 $ 0.19 Non-vested (4,218,833 ) 0.12 – 0.40 0.23 Vested, June 30, 2021 17,130,383 $0.12 – 0.43 $ 0.18 $ 250,000 Balance, December 31, 2019 9,214,356 $0.16 – 0.43 $ 0.25 Granted 8,610,689 0.17 – 0.22 0.19 Expired (200,000 ) 0.18 – 0.34 0.26 Balance, June 30, 2020 17,625,045 $0.16 – 0.43 $ 0.20 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 (1,453,855 ) 0.39 - 0.51 0.40 Balance, June 30, 2021 4,235,508 $0.23 - 1.65 $ 0.45 $ — Balance, December 31, 2019 8,769,451 $0.23 – 0.94 $ 0.42 Expired (930,000 ) 0.39 – 0.58 0.56 Balance, June 30, 2020 7,839,451 $0.23 – 1.65 $ 0.41 Weighted Non-plan average Aggregate Options Exercise price per Intrinsic outstanding price per share share value (1) Balance, December 31, 2020 20,749,583 $0.17 – 1.00 $ 0.41 Granted 43,956 0.23 0.23 Balance, June 30, 2021 20,793,539 $0.17 – 1.00 $ 0.41 Non-vested (1,996,576 ) 0.17 – 0.45 0.45 Vested, June 30, 2021 18,796,963 $0.17 – 1.00 $ 0.41 $ 28,000 Balance, December 31, 2019 19,604,107 $0.23 – 1.00 $ 0.41 Granted 292,437 0.17 – 0.21 0.18 Balance, June 30, 2020 19,896,544 $0.17 – 1.00 $ 0.41

Note 6 - Warrants (Tables)

Note 6 - Warrants (Tables)	6 Months Ended
	Jun. 30, 2021
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 $0.16 – 1.00 $ 0.29 Issued 7,088,094 0.14 – 0.26 0.20 Expired (1,046,528 ) 0.19 – 0.35 0.24 Balance, June 30, 2021 39,022,555 $0.14 – 1.00 $ 0.27 $ 140,000 Balance, December 31, 2019 43,231,161 $0.16 – 1.00 $ 0.42 Issued 3,934,592 0.13 - 0.24 0.13 Expired (14,272,820 ) 0.40 - 0.49 0.30 Balance, June 30, 2020 32,892,933 $0.16 – 1.00 $ 0.35
Schedule Of Assumptions Used To Determine Fair Value Of Warrants [Table Text Block]	June 30, 2021 June 30, 2020 Risk free interest rate 0.71% 0.23% Expected volatility 100% 112 Expected dividend yield — — Forfeiture rate — — Expected life in years .5 – 5 0.33 – 5

Note 7 - Accounts Payable and_2

Note 7 - Accounts Payable and Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2021
Notes Tables
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	June 30, 2021 December 31, 2020 Accounts payable and accrued expense $ 145 $ 315 Accrued interest 25 42 Accrued payroll 161 156 Total accounts payable and accrued expenses $ 331 $ 513

Note 9 - Noncontrolling Inter_2

Note 9 - Noncontrolling Interest - Clyra Medical (Tables)	6 Months Ended
	Jun. 30, 2021
Notes Tables
Schedule of Other Ownership Interests [Table Text Block]	Shareholder Shares Percent BioLargo, Inc. 49,207 45 % Sanatio Capital 18,704 17 % Scion Solutions(1) 21,700 20 % Other 19,280 18 % Total 108,891
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	June 30, 2021 December 31, 2020 Accounts payable and accrued expense $ 145 $ 315 Accrued interest 25 42 Accrued payroll 161 156 Total accounts payable and accrued expenses $ 331 $ 513
Clyra Medical [Member]
Notes Tables
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	June 30, 2021 December 31, 2020 Accounts payable and accrued expense $ 582 $ 402 Accrued interest 127 32 Accrued payroll 51 102 Total Clyra Medical accounts payable and accrued expenses $ 760 $ 536

Note 11 - Business Segment In_2

Note 11 - Business Segment Information (Tables)	6 Months Ended
	Jun. 30, 2021
Notes Tables
Schedule of Segment Reporting Information, by Segment [Table Text Block]	Three months ended June 30, Six months ended June 30, 2021 2020 2021 2020 Revenue BioLargo corporate $ — $ — $ 7 $ — ONM 318 299 638 596 BLEST 266 160 654 444 Water — — 9 — Clyra Medical — 21 114 21 Intersegment revenue (120 ) (62 ) (387 ) (205 ) Total $ 464 $ 418 $ 1,035 $ 856 Operating loss BioLargo corporate $ (937 ) $ (1,129 ) $ (1,860 ) $ (1,936 ) ONM (107 ) (134 ) (283 ) (287 ) Clyra Medical (300 ) (422 ) (739 ) (728 ) BLEST (190 ) (124 ) (373 ) (331 ) Water (168 ) (196 ) (305 ) (424 ) Total $ (1,702 ) $ (2,005 ) $ (3,560 ) $ (3,706 ) Interest expense BioLargo corporate $ (51 ) $ (735 ) $ (106 ) $ (1,479 ) Clyra Medical (38 ) (12 ) (76 ) (25 ) Total $ (89 ) $ (747 ) $ (182 ) $ (1,504 ) Research and development expense BioLargo corporate $ (209 ) $ (119 ) $ (545 ) $ (321 ) Clyra Medical (6 ) (47 ) (33 ) (61 ) BLEST (123 ) (85 ) (228 ) (166 ) Water (138 ) (137 ) (257 ) (317 ) Intersegment R&D 120 38 380 181 Total $ (356 ) $ (350 ) $ (683 ) $ (684 ) As June 30, 2021 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 1,072 $ 431 $ 1,016 $ 321 $ 151 $ (47 ) $ 2,944 Right of use 185 — — 126 — — 311 Investment in South Korean joint venture 40 — — — — — 40 Intangible assets 2,150 — — — — — 2,150 As of December 31, 2020 BioLargo ONM Clyra BLEST Water Elimination Total Tangible assets $ 603 $ 624 $ 1,125 $ 314 $ 105 $ (42 ) $ 2,388 Right of use 215 — — 126 — — 341 Investment in South Korean joint venture 63 — — — — — 63 Intangible assets 2,150 — — — — — 2,150

Note 1 - Business and Organiz_2

Note 1 - Business and Organization (Details Textual) - USD ($)	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Sep. 30, 2017
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total	$ (1,790,000)	$ (1,878,000)	$ (2,701,000)	$ (2,616,000)	$ (3,668,000)	$ (5,316,000)
Net Cash Provided by (Used in) Operating Activities, Total					(2,054,000)	(2,047,000)
Working Capital (Deficit)	380,000				380,000
Assets, Current, Total	2,052,000				2,052,000		$ 1,505,000
Revenue from Contract with Customer, Including Assessed Tax	464,000		$ 418,000		1,035,000	856,000
Cash and Cash Equivalents, at Carrying Value, Ending Balance	1,357,000				1,357,000		716,000
Repayments of Debt					852,000
Long-term Debt, Total	1,721,000				1,721,000
Long-term Line of Credit, Total	$ 0				0		$ 50,000
Proceeds from Issuance of Common Stock					3,520,000	1,461,000
Stock Issued During Period, Value, Issued for Unpaid Salary and Business Expenses					$ 31,000
Number of Wholly-Owned Subsidiaries	4				4
BioLargo Engineering, Science & Technologies, LLC [Member]
Noncontrolling Interest, Ownership Percentage by Parent	94.00%				94.00%			100.00%
Clyra Medical Technologies [Member]
Noncontrolling Interest, Ownership Percentage by Parent	45.00%				45.00%
The 2020 Unit Offering [Member]
Proceeds from Issuance of Common Stock					$ 505,000	242,000
Lincoln Park Capital Fund, LLC [Member]
Proceeds from Issuance of Common Stock					$ 3,015,000	$ 1,461,000
Sale of Stock, Daily Basis, Requirement, Minimum Share Price (in dollars per share)					$ 0.10
Debt Instrument, Excluding Debt from Clyra [Member]
Long-term Debt, Total	$ 514,000				$ 514,000
Paycheck Protection Program CARES Act [Member]
Long-term Debt, Total	314,000				314,000
Economic Injury Disaster Loan [Member]
Long-term Debt, Total	$ 150,000				$ 150,000
Debt Instrument, Interest Rate, Stated Percentage	3.75%				3.75%
Debt Instrument, Term (Year)					30 years
Convertible Debt due in March 2023 [Member]
Convertible Debt, Total	$ 50,000				$ 50,000
Clyra Medical Technology Inc [Member]
Long-term Debt, Total	1,207,000				1,207,000
Long-term Line of Credit, Total	$ 200,000				$ 200,000

Note 2 - Summary of Significa_3

Note 2 - Summary of Significant Accounting Policies (Details Textual)	Mar. 20, 2020USD ($)	Jun. 30, 2021USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2021USD ($)	Jun. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Accounts Receivable, Allowance for Credit Loss, Current		$ 12,000		$ 12,000		$ 13,000
Inventory Valuation Reserves, Ending Balance		3,000		3,000		3,000
Security Deposit		35,000		35,000
Payments to Acquire Interest in Joint Venture				0	$ 100,000
Income (Loss) from Equity Method Investments, Total				(23,000)	(15,000)
Impairment of Long-Lived Assets Held-for-use		0	$ 0	0	$ 0
Unrecognized Tax Benefits, Ending Balance		0		0		0
Operating Lease, Right-of-Use Asset		311,000		$ 311,000		$ 341,000
Canadian Government Grants [Member]
Number of Grants Received				80
Grants Receivable		$ 3,700,000		$ 3,700,000
Canadian Government Grants [Member] | Minimum [Member]
Grant Term (Month)				6 months
Canadian Government Grants [Member] | Maximum [Member]
Grant Term (Month)				18 months
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Number of Major Customers				3		2
Clyra Medical Technologies [Member]
Noncontrolling Interest, Ownership Percentage by Parent		45.00%		45.00%
Odin Co Ltd [Member]
Payments to Acquire Interest in Joint Venture	$ 100,000
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	40.00%	40.00%		40.00%
Income (Loss) from Equity Method Investments, Total		$ (10,000)		$ (23,000)
Odin Co Ltd [Member] | Tomorrow Water [Member]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	30.00%
Odin Co Ltd [Member] | BKT and Tomorrow Water [Member]
Payments to Acquire Interest in Joint Venture	$ 150,000

Note 2 - Summary of Significa_4

Note 2 - Summary of Significant Accounting Policies - Summary of Cash Balances (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Cash and Cash Equivalents, at Carrying Value, Ending Balance	$ 1,357,000	$ 716,000
Parent Company [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance	1,338,000	637,000
Noncontrolling Interest [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance	$ 19,000	$ 79,000

Note 2 - Summary of Significa_5

Note 2 - Summary of Significant Accounting Policies - Credit Concentration (Details) - Customer Concentration Risk [Member]	6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Customer A [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	22.00%
Customer C [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	11.00%
Customer C [Member] | Accounts Receivable [Member]
Credit concentration	31.00%
Customer B [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration	19.00%
Customer D [Member] | Revenue from Contract with Customer Benchmark [Member]
Credit concentration		13.00%
Customer D [Member] | Accounts Receivable [Member]
Credit concentration	17.00%
Customer E [Member] | Accounts Receivable [Member]
Credit concentration	11.00%
Customer F [Member] | Accounts Receivable [Member]
Credit concentration			32.00%
Customer G [Member] | Accounts Receivable [Member]
Credit concentration			10.00%

Note 2 - Summary of Significa_6

Note 2 - Summary of Significant Accounting Policies - Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Raw material	$ 91	$ 111
Finished goods	171	166
Total	$ 262	$ 277

Note 2 - Summary of Significa_7

Note 2 - Summary of Significant Accounting Policies - Stock Options, Valuation Assumptions (Details)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Non Plan [Member]
Risk free interest rate	1.73%	0.88%
Expected volatility	124.00%	131.00%
Expected dividend yield	0.00%	0.00%
Life in years (Year)	10 years	10 years
2018 Equity Incentive Plan [Member]
Expected dividend yield	0.00%	0.00%
Life in years (Year)	10 years	10 years
2018 Equity Incentive Plan [Member] | Minimum [Member]
Risk free interest rate	0.93%	0.88%
Expected volatility	123.00%	131.00%
2018 Equity Incentive Plan [Member] | Maximum [Member]
Risk free interest rate	1.73%	1.90%
Expected volatility	124.00%	133.00%

Note 3 - Sale of Stock for Ca_2

Note 3 - Sale of Stock for Cash (Details Textual) - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Mar. 30, 2020
Proceeds from Issuance of Common Stock	$ 3,520,000	$ 1,461,000
Warrants Issued in Connection with Investment from Three Investors [Member]
Warrants and Rights Outstanding, Term (Month)	6 months
Warrants Issued in Connection with Investment from Three Investors [Member] | Minimum [Member]
Warrants and Rights Outstanding, Term (Month)	6 months
Warrants Issued with 2020 Unit Offering [Member] | Maximum [Member]
Warrants and Rights Outstanding, Term (Month)	5 years
The 2020 Unit Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)	3,431,547	1,571,667
Proceeds from Issuance of Common Stock	$ 505,000	$ 242,000
Lincoln Park Capital Fund, LLC [Member]
Stock Purchase Agreement, Maximum Amount of Common Stock			$ 10,250,000
Stock Issued During Period, Shares, New Issues (in shares)	18,526,309	3,198,358
Proceeds from Issuance of Common Stock	$ 3,015,000	$ 1,461,000

Note 4 - Debt Obligations (Deta

Note 4 - Debt Obligations (Details Textual) - USD ($)	May 18, 2021	May 17, 2021	Apr. 20, 2021	Mar. 01, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Interest Expense, Debt, Total					$ 182,000	$ 1,504,000
Long-term Line of Credit, Total					0		$ 50,000
Debt Conversion, Original Debt, Amount					328,000	$ 1,122,000
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 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 August 18, 2021 [Member] | Conversion of Debt into Shares of Common Stock [Member]
Debt Conversion, Original Debt, Amount	$ 50,000
Debt Conversion, Converted Instrument, Shares Issued (in shares)	294,118
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
Note Payable, Maturing March 8, 2023 [Member]
Debt Instrument, Face Amount				$ 50,000	$ 50,000
Debt Instrument, Convertible, Conversion Price (in dollars per share)				$ 0.16

Note 4 - Debt Obligations - Sch

Note 4 - Debt Obligations - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Long-term Line of Credit, Total	$ 0	$ 50
Total notes payable and line of credit	0	100
Convertible notes	0	1,106
Debt discount, net of amortization	0	(104)
Total current liabilities	0	1,102
Long-term debt	485	507
Debt discount, net of amortization	(29)	0
Total	485	1,609
Note Payable, Maturing March 8, 2023 [Member]
Notes Payable, Current, Total	0	50
Convertible Note, Maturing April 20 2021 [Member]
Convertible notes	0	100
Convertible Note, Maturing August 9, 2021 [Member]
Convertible notes	0	600
Long-term debt	50	0
Convertible Notes, Maturing August 12 and 16, 2020 [Member]
Convertible notes	0	406
Paycheck Protection Program CARES Act [Member]
Long-term debt	314	357
Economic Injury Disaster Loan [Member]
Long-term debt	$ 150	$ 150

Note 5 - Share-based Compensa_3

Note 5 - Share-based Compensation (Details Textual) - USD ($)	Jun. 30, 2021	Mar. 31, 2021	Mar. 17, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 22, 2018	Sep. 07, 2017	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock Issued During Period, Value, Issued for Services										$ 60,000	$ 111,000	$ 272,000	$ 178,000
Stock Issued During Period, Value, New Issues										$ 1,414,000	$ 2,106,000	$ 560,000	$ 901,000
Share Price (in dollars per share)	$ 0.17								$ 0.17	$ 0.17				$ 0.17
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
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)														2,483,691	8,610,689
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)														$ 0.19	$ 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)														43,956	292,437
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)														$ 0.23	$ 0.18
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense														$ 754,000	$ 848,000
Common Stock Issued for Accrued Interest Due on Promissory Note [Member]
Shares Issued, Price Per Share (in dollars per share)	$ 0.17			$ 0.16	$ 0.17			$ 0.16	0.17	$ 0.17		$ 0.16	$ 0.17	$ 0.17	$ 0.16
Stock Issued During Period, Shares, New Issues (in shares)										81,777			19,278		594,428
Stock Issued During Period, Value, New Issues										$ 16,000			$ 4,000		$ 30,000
Officer [Member]
Stock Issued During Period, Shares, Issued for Services (in shares)		137,364			648,755			367,403
Shares Issued, Price Per Share (in dollars per share)		$ 0.23		$ 0.16	$ 0.17			$ 0.16			$ 0.23	0.16	$ 0.17		$ 0.16
Stock Issued During Period, Value, Issued for Services		$ 31,000			$ 110,000			$ 59,000
Consultants [Member]
Stock Issued During Period, Shares, Issued for Services (in shares)	357,132	610,123		1,406,630	390,735
Shares Issued, Price Per Share (in dollars per share)	$ 0.17	$ 0.23		$ 0.16	$ 0.17			$ 0.16	$ 0.17	$ 0.17	$ 0.23	0.16	$ 0.17	$ 0.17	$ 0.16
Stock Issued During Period, Value, Issued for Services	$ 60,000	$ 81,000		$ 213,000	$ 67,000
Consultants [Member] | 2018 Equity Incentive Plan [Member]
Stock Issued During Period, Value, Issued for Services															$ 65,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)															449,286
Employees, Consultations, 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)														2,483,691	8,610,689
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	457,500
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)			$ 0.23											$ 0.17
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares (in shares)									125,000						177,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value			$ 49,000
Engagement Agreement, Term (Month)			12 months
Chief Financial Officer [Member] | 2018 Equity Incentive Plan [Member] | Vesting Monthly [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)			175,000												25,000
Chief Financial Officer [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)															$ 0.14
Chief Financial Officer [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)															$ 0.21
Board Of Directors [Member] | 2018 Equity Incentive Plan [Member]
Share-based Payment Arrangement, Expense														$ 130,000	$ 130,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)														693,762	821,434
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)														$ 0.17	$ 0.17
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)														$ 0.23	$ 0.16
Employees [Member] | 2018 Equity Incentive Plan [Member]
Share-based Payment Arrangement, Expense														$ 234,000	$ 151,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)														1,298,411	939,332
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)														4 years	4 years
Employees [Member] | 2018 Equity Incentive Plan [Member] | Converted Accrued and Unpaid Obligations for Previous Issued Expired Options [Member]
Share-based Payment Arrangement, Expense															$ 145,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)															1,062,192
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)														$ 0.17	$ 0.16
Employees [Member] | 2018 Equity Incentive Plan [Member] | Minimum [Member] | Converted Accrued and Unpaid Obligations for Previous Issued Expired Options [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)															0.14
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)														$ 0.23	0.17
Employees [Member] | 2018 Equity Incentive Plan [Member] | Maximum [Member] | Converted Accrued and Unpaid Obligations for Previous Issued Expired Options [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)															$ 0.17
Employees and Consultants [Member] | 2018 Equity Incentive Plan [Member]
Stock Issued During Period, Value, Issued for Services														$ 35,000
Share-based Payment Arrangement, Expense															$ 656,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)														191,518	4,880,945
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)															$ 0.14
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)															1 year
Vendors [Member] | Non Plan [Member]
Shares Issued, Price Per Share (in dollars per share)	$ 0.23								$ 0.23	$ 0.23				$ 0.23
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)														43,956	292,437
Vendors [Member] | Non Plan [Member] | Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense														$ 10,000	$ 50,000
Vendors [Member] | Non Plan [Member] | Minimum [Member]
Shares Issued, Price Per Share (in dollars per share)				$ 0.17				0.17				0.17			$ 0.17
Vendors [Member] | Non Plan [Member] | Maximum [Member]
Shares Issued, Price Per Share (in dollars per share)				$ 0.21				$ 0.21				$ 0.21			$ 0.21

Note 5 - Share-based Compensa_4

Note 5 - Share-based Compensation - Stock Options (Details) - USD ($)		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020
2018 Equity Incentive Plan [Member]
Options outstanding, balance (in shares)		18,865,525	9,214,356
Weighted average exercise price per share, balance (in dollars per share)		$ 0.19	$ 0.25
Options granted (in shares)		2,483,691	8,610,689
Weighted average exercise price per share, granted (in dollars per share)		$ 0.19	$ 0.19
Options expired (in shares)		0	(200,000)
Weighted average exercise price per share, Expired (in dollars per share)		$ 0	$ 0.26
Options Non-vested (in shares)		(4,218,833)
Weighted average exercise price per share, Non-vested (in dollars per share)		$ 0.23
Options Vested (in shares)		17,130,383
Vested, June 30, 2021 (in dollars per share)		$ 0.18
Vested, aggregate intrinsic value	[1]	$ 250,000
Options outstanding, balance (in shares)		21,349,216	17,625,045
Weighted average exercise price per share, balance (in dollars per share)		$ 0.19	$ 0.20
2018 Equity Incentive Plan [Member] | Minimum [Member]
Exercise price per share, balance (in dollars per share)		0.16	0.16
Exercise price per share, granted (in dollars per share)		0.13	0.17
Exercise price per share, Non-vested (in dollars per share)		0.12
Exercise price per share, Vested (in dollars per share)		0.12
Exercise price per share, Expired (in dollars per share)			0.18
Exercise price per share, balance (in dollars per share)		0.12	0.16
2018 Equity Incentive Plan [Member] | Maximum [Member]
Exercise price per share, balance (in dollars per share)		0.40	0.43
Exercise price per share, granted (in dollars per share)		0.23	0.22
Exercise price per share, Non-vested (in dollars per share)		0.40
Exercise price per share, Vested (in dollars per share)		0.43
Exercise price per share, Expired (in dollars per share)			0.34
Exercise price per share, balance (in dollars per share)		$ 0.43	$ 0.43
The 2007 Equity Incentive Plan [Member]
Options outstanding, balance (in shares)		5,689,363	8,769,451
Weighted average exercise price per share, balance (in dollars per share)		$ 0.44	$ 0.42
Options expired (in shares)		(1,453,855)	(930,000)
Weighted average exercise price per share, Expired (in dollars per share)		$ 0.40	$ 0.56
Options outstanding, balance (in shares)		4,235,508	7,839,451
Weighted average exercise price per share, balance (in dollars per share)		$ 0.45	$ 0.41
Outstanding, aggregate intrinsic value	[1]
The 2007 Equity Incentive Plan [Member] | Minimum [Member]
Exercise price per share, balance (in dollars per share)		0.23	$ 0.23
Exercise price per share, Expired (in dollars per share)		0.39	0.39
Exercise price per share, balance (in dollars per share)		0.23	0.23
The 2007 Equity Incentive Plan [Member] | Maximum [Member]
Exercise price per share, balance (in dollars per share)		0.94	0.94
Exercise price per share, Expired (in dollars per share)		0.51	0.58
Exercise price per share, balance (in dollars per share)		$ 1.65	$ 1.65
Non Plan [Member]
Options outstanding, balance (in shares)		20,749,583	19,604,107
Weighted average exercise price per share, balance (in dollars per share)		$ 0.41	$ 0.41
Options granted (in shares)		43,956	292,437
Exercise price per share, granted (in dollars per share)		$ 0.23
Weighted average exercise price per share, granted (in dollars per share)		$ 0.23	$ 0.18
Options Non-vested (in shares)		(1,996,576)
Weighted average exercise price per share, Non-vested (in dollars per share)		$ 0.45
Options Vested (in shares)		18,796,963
Vested, June 30, 2021 (in dollars per share)		$ 0.41
Vested, aggregate intrinsic value	[1]	$ 28,000
Options outstanding, balance (in shares)		20,793,539	19,896,544
Weighted average exercise price per share, balance (in dollars per share)		$ 0.41	$ 0.41
Non Plan [Member] | Minimum [Member]
Exercise price per share, balance (in dollars per share)		0.17	0.23
Exercise price per share, granted (in dollars per share)			0.17
Exercise price per share, Non-vested (in dollars per share)		0.17
Exercise price per share, Vested (in dollars per share)		0.17
Exercise price per share, balance (in dollars per share)		0.17	0.17
Non Plan [Member] | Maximum [Member]
Exercise price per share, balance (in dollars per share)		1	1
Exercise price per share, granted (in dollars per share)			0.21
Exercise price per share, Non-vested (in dollars per share)		0.45
Exercise price per share, Vested (in dollars per share)		1
Exercise price per share, balance (in dollars per share)		$ 1	$ 1
[1]	Aggregate intrinsic value based on closing common stock price of $0.17 at June 30, 2021

Note 6 - Warrants (Details Text

Note 6 - Warrants (Details Textual) - USD ($)	Mar. 01, 2021	Jun. 30, 2021
Share Price (in dollars per share)		$ 0.17
Note Payable, Maturing March 8, 2023 [Member]
Debt Instrument, Face Amount	$ 50,000	$ 50,000
Debt Instrument, Term (Year)	2 years
Warrants Issued in Connection with Investment from Three Investors [Member]
Warrants and Rights Outstanding, Term (Month)		6 months
Class of Warrant or Right, Issued During Period, Number of Securities Called by Warrants or Rights (in shares)		3,431,547
Warrants Issued in Connection with Investment from Three Investors [Member] | Minimum [Member]
Warrants and Rights Outstanding, Term (Month)		6 months
Class of Warrant or Right, Issued During Period, Exercise Price (in dollars per share)		$ 0.14
Warrants Issued in Connection with Investment from Three Investors [Member] | Maximum [Member]
Class of Warrant or Right, Issued During Period, Exercise Price (in dollars per share)		$ 0.21
Five Year Warrant [Member]
Warrants and Rights Outstanding, Term (Month)		5 years
Class of Warrant or Right, Issued During Period, Number of Securities Called by Warrants or Rights (in shares)		3,431,547
Five Year Warrant [Member] | Minimum [Member]
Class of Warrant or Right, Issued During Period, Exercise Price (in dollars per share)		$ 0.18
Five Year Warrant [Member] | Maximum [Member]
Class of Warrant or Right, Issued During Period, Exercise Price (in dollars per share)		$ 0.24
Warrants Issued in Connection with Conversion of Interest on Note Payable Maturing March 8, 2023 [Member]
Warrants and Rights Outstanding, Term (Month)	5 years
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (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 ($)		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020
Balance, outstanding (in shares)		32,980,989	43,231,161
Issued (in shares)		7,088,094	3,934,592
Expired (in shares)		(1,046,528)	(14,272,820)
Balance, outstanding (in shares)		39,022,555	32,892,933
Balance, aggregate intrinsic value	[1]	$ 140,000
Minimum [Member]
Balance, outstanding, price range (in dollars per share)		$ 0.16	$ 0.16
Granted, price range (in dollars per share)		0.14	0.13
Expired (in dollars per share)		0.19	0.40
Balance, outstanding, price range (in dollars per share)		0.14	0.16
Maximum [Member]
Balance, outstanding, price range (in dollars per share)		1	1
Granted, price range (in dollars per share)		0.26	0.24
Expired (in dollars per share)		0.35	0.49
Balance, outstanding, price range (in dollars per share)		1	1
Weighted Average [Member]
Balance, outstanding, price range (in dollars per share)		0.29	0.42
Granted, price range (in dollars per share)		0.20	0.13
Expired (in dollars per share)		0.24	0.30
Balance, outstanding, price range (in dollars per share)		$ 0.27	$ 0.35
[1]	Aggregate intrinsic value based on closing common stock price of $0.17 at June 30, 2021

Note 6 - Warrants - Assumptions

Note 6 - Warrants - Assumptions Used to Determine Fair Value of Warrants (Details)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Risk free interest rate	0.71%	0.23%
Expected volatility	100.00%	112.00%
Minimum [Member]
Expected life (Year)	6 months	3 months 29 days
Maximum [Member]
Expected life (Year)	5 years	5 years

Note 7 - Accounts Payable and_3

Note 7 - Accounts Payable and Accrued Expenses - Summary of Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Corporate, Non-Segment [Member]
Accounts payable and accrued expense	$ 145
Accrued interest	25
Accrued payroll	161
Total accounts payable and accrued expenses	$ 331
Operating Segments [Member] | Odor-No-More [Member]
Accounts payable and accrued expense		$ 315
Accrued interest		42
Accrued payroll		156
Total accounts payable and accrued expenses		$ 513

Note 9 - Noncontrolling Inter_3

Note 9 - Noncontrolling Interest - Clyra Medical (Details Textual) - USD ($)	Mar. 01, 2022	Jun. 30, 2020	Dec. 17, 2018	Sep. 26, 2018	Dec. 30, 2015	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Feb. 28, 2022	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Dec. 31, 2020
Long-term Line of Credit, Total						$ 0					$ 0		$ 0	$ 50,000
Stock Issued During Period, Value, Issued for Services						60,000	$ 111,000	$ 272,000	$ 178,000
Stock Issued During Period, Value, New Issues						$ 1,414,000	$ 2,106,000	$ 560,000	$ 901,000
Share Price (in dollars per share)						$ 0.17					$ 0.17		$ 0.17
Clyra Medical [Member]
Stock Issued During Period, Value, New Issues											$ 50,000	$ 849,000
Shares Issued, Price Per Share (in dollars per share)		$ 310				$ 310		$ 310			$ 310	$ 310	$ 310
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)		1,945				1,248		1,945			1,248	1,945	1,248	11,411
Share Price (in dollars per share)						$ 310					$ 310		$ 310
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
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)											10 years
Clyra Medical [Member] | Vendors and Employees [Member] | Share-based Payment Arrangement, Option [Member]
Stock Issued During Period, Value, Issued for Services											$ 263,000	$ 441,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Discount Rate											30.00%
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
Consulting Services, Three Consecutive Month Average Revenue Threshold for Consulting Fees to Accrue											$ 250,000
Stock Issued During Period, Value, Issued for Services											788,000
Clyra Medical [Member] | Revolving Credit Facility [Member] | Vernal Bay Capital Group, LLC [Member] | Inventory Line of Credit [Member]
Debt Instrument, Interest Rate, Stated Percentage		15.00%						15.00%				15.00%
Debt Instrument, Term (Year)		1 year
Line of Credit Facility, Maximum Borrowing Capacity		$ 1,000,000						$ 1,000,000				$ 1,000,000
Proceeds from Lines of Credit, Total													$ 260,000
Line of Credit Facility, Covenant, Additional Draws, Maximum Percentage of Total Principal Outstanding Allowed		50.00%						50.00%				50.00%
Line of Credit Facility, Covenant, Additional Draws, Minimum Amount Allowed		$ 200,000						$ 200,000				$ 200,000
Line of Credit Facility, Monthly Percentage of Gross Product Sales Required to be Used as Payment of Debt on First 180 Days		30.00%						30.00%				30.00%
Line of Credit Facility, Monthly Percentage of Gross Product Sales Required to be Used as Payment of Debt after the First 180 Days		60.00%						60.00%				60.00%
Stock Issued During Period, Shares, Commitment Fee (in shares)		323
Stock Issued During Period, Value, Commitment Fee		$ 70,000
Repayments of Lines of Credit											24,000
Long-term Line of Credit, Total						$ 200,000					$ 200,000		$ 200,000
Clyra Medical [Member] | Revolving Credit Facility [Member] | Vernal Bay Capital Group, LLC [Member] | Inventory Line of Credit [Member] | Forecast [Member]
Debt Instrument, Periodic Payment, Percentage of Sales	60.00%									40.00%
Clyra Medical [Member] | Revolving Credit Facility [Member] | Vernal Bay Capital Group, LLC [Member] | Inventory Line of Credit [Member] | Minimum [Member] | Forecast [Member]
Debt Instrument, Periodic Payment, Principal	$ 7,500									$ 7,500
Clyra Medical [Member] | Scion Acquisition [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)				21,000
Business Combination, Consideration Transferred, Liabilities Incurred				$ 1,250,000
Business Acquisition, Base Capital Requirement for Escrow Release			$ 1,000,000	$ 1,000,000
Business Acquisition, Gross Revenue, Tranche One			100,000
Business Acquisition, Gross Revenue, Tranche Two			100,000
Business Acquisition, Gross Revenue, Tranche Three			500,000
Business Acquisition, Gross Revenue, Tranche Five			$ 2,000,000
Shares Remaining in Escrow (in shares)						9,300					9,300		9,300
Clyra Medical [Member] | Scion Acquisition [Member] | Clyra Acquisition, Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)				10,000
Clyra Medical [Member] | Scion Acquisition [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
Clyra Medical [Member] | Scion Solutions [Member]
Debt Instrument, Interest Rate, Stated Percentage				5.00%
Debt Instrument, Percent of Investment Proceeds				25.00%
Debt Instrument, Percent of Gross Revenue				5.00%
Notes Payable, Current, Total						$ 1,007,000					$ 1,007,000		$ 1,007,000	$ 1,007,000
Clyra Medical [Member] | Clyra Acquisition, Common Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)											9,300
Clyra Medical Technologies [Member]
Noncontrolling Interest, Ownership Percentage by Parent						45.00%					45.00%		45.00%

Note 9 - Noncontrolling Inter_4

Note 9 - Noncontrolling Interest - Clyra Medical Common and Preferred Shares Outstanding (Details) - Clyra Medical Technology Inc [Member]	Jun. 30, 2021shares
Shares, Outstanding (in shares)	108,891
Biolargo [Member]
Shares, Outstanding (in shares)	49,207
Percent	45.00%
Sanatio [Member]
Shares, Outstanding (in shares)	18,704
Percent	17.00%
Scion Solutions [Member]
Shares, Outstanding (in shares)	21,700	[1]
Percent	20.00%	[1]
Other [Member]
Shares, Outstanding (in shares)	19,280
Percent	18.00%
[1]	The above amounts do not include an additional 9,300 shares held in escrow subject to performance metrics that have not been met.

Note 9 - Noncontrolling Inter_5

Note 9 - Noncontrolling Interest - Summary of Accounts Payable and Accrued Expenses (Details) - Clyra Medical [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts payable and accrued expense	$ 582	$ 402
Accrued interest	127	32
Accrued payroll	51	102
Total accounts payable and accrued expenses	$ 760	$ 536

Note 10 - BioLargo Engineerin_2

Note 10 - BioLargo Engineering, Science and Technologies, LLC (Details Textual) - USD ($)	1 Months Ended			6 Months Ended		12 Months Ended
	Jan. 31, 2021	Nov. 30, 2019	Sep. 30, 2017	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense, Total				$ 1,017,000	$ 1,074,000
Percentage of Profits Interests Vested		2.50%
Percentage of Option to Purchase Shares of Common Stock		10.00%
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			30.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	262,500	175,000
Incentive Issuance Stipulations for Subsidiary Employees, Accounts Receivable Collected by Year One of Operation			90.00%
Incentive Issuance Stipulations for Subsidiary Employees, Profit Earned in Year One of Operation			10.00%
Percentage of Profits Interests Vested	3.75%
Percentage of Option to Purchase Shares of Common Stock	15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value		$ 44,000		$ 0		$ 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			100.00%	94.00%

Note 11 - Business Segment In_3

Note 11 - Business Segment Information (Details Textual)	6 Months Ended
	Jun. 30, 2021
Number of Operating Segments	4

Note 11 - Business Segment In_4

Note 11 - Business Segment Information - Segment Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Revenue	$ 464,000	$ 418,000	$ 1,035,000	$ 856,000
Operating loss	(1,702,000)	(2,005,000)	(3,560,000)	(3,706,000)
Interest expense	(89,000)	(747,000)	(182,000)	(1,504,000)
Research and development	(356,000)	(350,000)	(683,000)	(684,000)
Tangible assets	2,944,000		2,944,000		$ 2,388,000
Operating Lease, Right-of-Use Asset	311,000		311,000		341,000
Investment in South Korean joint venture	40,000		40,000		63,000
Intangible assets	2,150,000		2,150,000		2,150,000
Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	40,000		40,000		63,000
Corporate, Non-Segment [Member]
Revenue	0	0	7,000	0
Operating loss	(937,000)	(1,129,000)	(1,860,000)	(1,936,000)
Interest expense	(51,000)	(735,000)	(106,000)	(1,479,000)
Research and development	(209,000)	(119,000)	(545,000)	(321,000)
Tangible assets	1,072,000		1,072,000		603,000
Operating Lease, Right-of-Use Asset	185,000		185,000		215,000
Intangible assets	2,150,000		2,150,000		2,150,000
Corporate, Non-Segment [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	40,000		40,000		63,000
Operating Segments [Member] | Odor-No-More [Member]
Revenue	318,000	299,000	638,000	596,000
Operating loss	(107,000)	(134,000)	(283,000)	(287,000)
Tangible assets	431,000		431,000		624,000
Operating Lease, Right-of-Use Asset	0		0		0
Intangible assets	0		0		0
Operating Segments [Member] | Odor-No-More [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0		0		0
Operating Segments [Member] | Clyra Medical [Member]
Tangible assets	1,016,000		1,016,000		1,125,000
Operating Lease, Right-of-Use Asset	0		0		0
Intangible assets	0		0		0
Operating Segments [Member] | Clyra Medical [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0		0		0
Operating Segments [Member] | BLEST [Member]
Tangible assets	321,000		321,000		314,000
Operating Lease, Right-of-Use Asset	126,000		126,000		126,000
Intangible assets	0		0		0
Operating Segments [Member] | BLEST [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0		0		0
Operating Segments [Member] | BioLargo Water [Member]
Revenue	0	0	9,000	0
Operating loss	(168,000)	(196,000)	(305,000)	(424,000)
Research and development	(138,000)	(137,000)	(257,000)	(317,000)
Tangible assets	151,000		151,000		105,000
Operating Lease, Right-of-Use Asset	0		0		0
Intangible assets	0		0		0
Operating Segments [Member] | BioLargo Water [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	0		0		0
Operating Segments [Member] | BioLargo Engineering, Science & Technologies, LLC [Member]
Revenue	266,000	160,000	654,000	444,000
Operating loss	(190,000)	(124,000)	(373,000)	(331,000)
Research and development	(123,000)	(85,000)	(228,000)	(166,000)
Operating Segments [Member] | Clyra Segment [Member]
Revenue	0	21,000	114,000	21,000
Operating loss	(300,000)	(422,000)	(739,000)	(728,000)
Interest expense	(38,000)	(12,000)	(76,000)	(25,000)
Research and development	(6,000)	(47,000)	(33,000)	(61,000)
Consolidation, Eliminations [Member]
Revenue	(120,000)	(62,000)	(387,000)	(205,000)
Research and development	120,000	$ 38,000	380,000	$ 181,000
Tangible assets	(47,000)		(47,000)		(42,000)
Operating Lease, Right-of-Use Asset	0		0		0
Intangible assets	0		0		0
Consolidation, Eliminations [Member] | Investment in South Korean Joint Venture [Member]
Investment in South Korean joint venture	$ 0		$ 0		$ 0

Note 12 - Commitments and Con_2

Note 12 - Commitments and Contingencies (Details Textual) - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Operating Lease, Expense	$ 113,000	$ 114,000
Operating Lease, Weighted Average Remaining Lease Term (Year)	3 years
Lessee, Operating Lease, Liability, to be Paid, Total	$ 434,000
Lessee, Operating Lease, Discount Rate	18.00%
Corporate Office Lease [Member]
Lessee Operating, Lease Annual Escalation Rate	3.00%
Lessee, Operating Lease, Renewal Term (Year)	4 years
Oak Ridge, Tennessee Facility Lease [Member]
Lessee, Operating Lease, Renewal Term (Year)	5 years
Lessee, Operating Lease, Option to Extend Term (Year)	3 years

Note 13 - Subsequent Events (De

Note 13 - Subsequent Events (Details Textual) - USD ($)	1 Months Ended		6 Months Ended
	Aug. 12, 2021	Aug. 09, 2021	Jun. 30, 2021	Jun. 30, 2020
Proceeds from Issuance of Common Stock			$ 3,520,000	$ 1,461,000
Lincoln Park Capital Fund, LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares)			18,526,309	3,198,358
Proceeds from Issuance of Common Stock			$ 3,015,000	$ 1,461,000
Subsequent Event [Member] | Six-month Warrants in Connection With the 2020 Unit Offering [Member]
Warrants and Rights Outstanding, Term (Month)	6 months
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	388,889
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.216
Subsequent Event [Member] | Five-year Warrants in Connection With the 2020 Unit Offering [Member]
Warrants and Rights Outstanding, Term (Month)	5 years
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	388,889
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.27
Subsequent Event [Member] | Lincoln Park Capital Fund, LLC [Member]
Stock Issued During Period, Shares, New Issues (in shares)		884,391
Proceeds from Issuance of Common Stock		$ 164,000
Subsequent Event [Member] | The 2020 Unit Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)	388,889
Proceeds from Issuance of Common Stock	$ 70,000