Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Cash flows from operating activities
Net loss	$ (11,047,000)	$ (2,615,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Credit loss expense	3,849,000	0
Stock option compensation expense	1,951,000	1,264,000
Common stock issued for services	388,000	365,000
Bad debt expense	37,000	13,000
PPP loan forgiveness	0	(97,000)
Amortization of debt discount	106,000	0
Amortization of right-of-use operating lease assets	106,000	73,000
Amortization of right-of-use finance lease asset	51,000	0
Operating lease liabilities	(100,000)	(60,000)
Finance lease liability	(65,000)	0
(Gain) loss on investment in South Korean joint venture	(9,000)	4,000
Depreciation expense	112,000	115,000
Changes in assets and liabilities:
Accounts receivable	(1,958,000)	(610,000)
Inventories	(79,000)	(85,000)
Prepaid expenses and other assets	11,000	(7,000)
Deposits	(10,000)	(35,000)
Contract liabilities	0	(284,000)
Net cash used in operating activities	(6,707,000)	(1,290,000)
Cash flows from investing activities
Equipment purchases	(33,000)	(1,260,000)
Proceeds from note receivable	481,000	0
Net cash provided by (used in) investing activities	448,000	(1,260,000)
Cash flows from financing activities
Proceeds from sale of common stock, net of commissions	1,542,000	609,000
Proceeds from debt obligation	50,000	0
Proceeds from warrant exercise	0	756,000
Proceeds from option exercise	0	153,000
Proceeds from sale of common stock		349,000
Repayment of debt obligations	(18,000)	(12,000)
Proceeds from Clyra Medical debt obligations	1,261,000	0
Net cash provided by financing activities	7,269,000	2,846,000
Net effect of foreign currency translation	(12,000)	47,000
Net change in cash	998,000	343,000
Cash and cash equivalents at beginning of period	3,548,000	3,539,000
Cash and cash equivalents at end of period	4,546,000	3,882,000
Supplemental disclosures of cash flow information
Interest	246,000	12,000
Income taxes	0	0
Short-term lease payments not included in lease liabilities	21,000	37,000
Non-cash investing and financing activities
Conversion of accounts receivable to a note receivable	3,764,000	0
Allocation of noncontrolling interest	3,346,000	84,000
Fair value of Clyra Medical warrants issued as debt discount	162,000	0
Clyra Medical dividend Series A Preferred stock	259,000	259,000
Conversion of BETI Common Stock to BioLargo Common Stock [Member]
Non-cash investing and financing activities
Conversion of BETI common stock to BioLargo common stock	25,000	50,000
Conversion of Debt into Shares of Common Stock [Member]
Non-cash investing and financing activities
Conversion of Clyra note payable into Clyra shares	0	119,000
BioLargo Energy Technologies, Inc (BETI) [Member]
Cash flows from financing activities
Proceeds from BETI unit offering	100,000	0
Clyra Medical Technologies [Member]
Cash flows from financing activities
Proceeds from warrant exercise	1,894,000	0
Non-cash investing and financing activities
Clyra Medical right-of-use asset and operating lease liability	184,000	0
BETI Common Stock [Member]
Cash flows from financing activities
Proceeds from sale of common stock	0	50,000
Clyra Medical Preferred Stock, Series B [Member]
Cash flows from financing activities
Proceeds from Clyra Medical preferred series B	2,145,000	0
Clyra Medical Common Stock [Member]
Cash flows from financing activities
Proceeds from sale of common stock	295,000	1,290,000
Entities, Excluding Partially Owned Subsidiary [Member]
Changes in assets and liabilities:
Accounts payable and accrued expenses	(55,000)	118,000
Partially Owned Subsidiary [Member]
Changes in assets and liabilities:
Accounts payable and accrued expenses	$ 5,000	$ 551,000