v3.25.2
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2025
Aug. 08, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Amendment Flag false  
Document Period End Date Jun. 30, 2025  
Document Fiscal Year Focus 2025  
Current Fiscal Year End Date --12-31  
Document Fiscal Period Focus Q2  
Entity File Number 001-39062  
Entity Registrant Name Korro Bio, Inc.  
Entity Central Index Key 0001703647  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 47-2324450  
Entity Address, Address Line One 60 First Street  
Entity Filer Category Non-accelerated Filer  
Entity Emerging Growth Company false  
Entity Address, Address Line Two 2nd Floor  
Entity Address, Address Line Three Suite 250  
Entity Address, City or Town Cambridge  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02141  
City Area Code 617  
Local Phone Number 468-1999  
Title of 12(b) Security Common Stock, par value $0.001 per share  
Trading Symbol KRRO  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Document Transition Report false  
Entity Small Business true  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   9,390,903