v3.25.2
Cover - shares
 6 Months Ended
Jun. 30, 2025
Aug. 06, 2025
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-40223  
Entity Registrant Name Bolt Projects Holdings, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 86-1256660  
Entity Address, Address Line One 2261 Market Street  
Entity Address, Address Line Two Suite 5547  
Entity Address, City or Town San Francisco  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 94114  
City Area Code (415)  
Local Phone Number 325-5912  
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  
Entity Ex Transition Period false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   2,061,779
Entity Central Index Key 0001841125  
Amendment Flag false  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Current Fiscal Year End Date --12-31  
Common Stock    
Document Information [Line Items]    
Title of 12(b) Security Common stock, par value $0.0001 per share  
Trading Symbol BSLK  
Security Exchange Name NASDAQ  
Warrants    
Document Information [Line Items]    
Title of 12(b) Security Warrants, each 20 whole warrants exercisable for one share of common stock at an exercise price of $230.00  
Trading Symbol BSLKW  
Security Exchange Name NASDAQ