Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

Document and Entity Information - shares
6 Months Ended
Jun. 30, 2021
Aug. 09, 2021
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 30, 2021  
Document Fiscal Year Focus 2021  
Document Fiscal Period Focus Q2  
Entity Registrant Name GRAPHITE BIO, INC.  
Entity Central Index Key 0001815776  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Shell Company false  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Current Reporting Status No  
Entity Interactive Data Current Yes  
Entity Incorporation State Country Code DE  
Entity Address Address Line1 279 East Grand Avenue  
Entity Address, Address Line Two Suite 430  
Entity Address City Or Town South San Francisco  
Entity Address State Or Province CA  
Entity Address Postal Zip Code 94080  
City Area Code 650  
Local Phone Number 484-0886  
Entity File Number 001-40532  
Entity Tax Identification Number 84-4867570  
Security12b Title Common Stock, par value $0.00001 per share  
Trading Symbol GRPH  
Security Exchange Name NASDAQ  
Document Quarterly Report true  
Document Transition Report false  
Entity Common Stock, Shares Outstanding   58,079,002