General form for registration of securities under the Securities Act of 1933

Cover

v3.25.3
Cover
9 Months Ended
Sep. 30, 2025
Cover [Abstract]  
Document Type S-1/A
Amendment Flag true
Amendment Description Client made date edits
Entity Registrant Name FOCUS UNIVERSAL INC.
Entity Central Index Key 0001590418
Entity Tax Identification Number 46-3355876
Entity Incorporation, State or Country Code NV
Entity Address, Address Line One 2311 East Locust Court
Entity Address, City or Town Ontario
Entity Address, State or Province CA
Entity Address, Postal Zip Code 91761
City Area Code 626
Local Phone Number 272-3883
Entity Filer Category Non-accelerated Filer
Entity Small Business true
Entity Emerging Growth Company false