v3.26.1
Document And Entity Information
 12 Months Ended
Dec. 31, 2025
Document Information [Line Items]  
Entity Central Index Key 0000880242
Entity Registrant Name BIOLARGO, INC.
Amendment Flag false
Document Type S-1
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
Entity Small Business true
Entity Emerging Growth Company false
Entity Filer Category Non-accelerated Filer