v3.26.1
Cover - USD ($)
 12 Months Ended
Dec. 31, 2025
Feb. 28, 2026
Jun. 30, 2025
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Dec. 31, 2025    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2025    
Current Fiscal Year End Date --12-31    
Entity File Number 1-03480    
Entity Registrant Name WISDOMTREE BITCOIN FUND    
Entity Central Index Key 0001850391    
Entity Tax Identification Number 99-6119726    
Entity Incorporation, State or Country Code DE    
Entity Address, Address Line One 250 West 34th Street    
Entity Address, Address Line Two 3rd Floor    
Entity Address, City or Town New York    
Entity Address, State or Province NY    
Entity Address, Postal Zip Code 10119    
City Area Code 866    
Local Phone Number 909-9473    
Title of 12(b) Security Common Shares of Beneficial Interest of WisdomTree Bitcoin Fund    
Trading Symbol BTCW    
Security Exchange Name CboeBZX    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
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 Public Float     $ 152,964,909
Entity Common Stock, Shares Outstanding   1,825,000  
Documents Incorporated by Reference [Text Block] None    
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction [Flag] false    
Auditor Firm ID 42    
Auditor Name Ernst & Young LLP    
Auditor Location New York, New York