| Document And Entity Information | Nov. 04, 2022 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 04, 2022 |
| Entity Registrant Name | Fast Radius, Inc. |
| Entity Central Index Key | 0001832351 |
| Entity Emerging Growth Company | true |
| Securities Act File Number | 001-40032 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 85-3692788 |
| Entity Address, Address Line One | 113 N. May Street |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60607 |
| City Area Code | (312) |
| Local Phone Number | 319-1060 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Ex Transition Period | false |
| Common Stock [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Common stock, par value $0.0001 per share |
| Trading Symbol | FSRD |
| Security Exchange Name | NASDAQ |
| Common Stock Warrant [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Warrants, each whole warrant exercisable for one share of common stock at an exercise price of $11.50 per share |
| Trading Symbol | FSRDW |
| Security Exchange Name | NASDAQ |
