Quarterly report pursuant to Section 13 or 15(d)


Cover - shares
6 Months Ended
Jun. 30, 2021
Aug. 16, 2021
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Quarterly Report true  
Document Transition Report false  
Document Period End Date Jun. 30, 2021  
Document Fiscal Period Focus Q2  
Document Fiscal Year Focus 2021  
Current Fiscal Year End Date --12-31  
Entity File Number 000-55247  
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 E. Locust St.  
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 Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Elected Not To Use the Extended Transition Period false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   40,959,741