| Document And Entity Information | Mar. 21, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Mar. 21, 2024 |
| Entity Registrant Name | CARGO Therapeutics, Inc. |
| Entity Central Index Key | 0001966494 |
| Entity Emerging Growth Company | true |
| Entity File Number | 001-41859 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 84-4080422 |
| Entity Address, Address Line One | 1900 Alameda De Las Pulgas |
| Entity Address, Address Line Two | Suite 350 |
| Entity Address, City or Town | San Mateo |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94403 |
| City Area Code | (650) |
| Local Phone Number | 379-6143 |
| Entity Information, Former Legal or Registered Name | N/A |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Ex Transition Period | false |
| Title of 12(b) Security | Common stock, par value $0.001 per share |
| Trading Symbol | CRGX |
| Security Exchange Name | NASDAQ |
