| Document and Entity Information | Apr. 02, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Apr. 02, 2023 |
| Entity File Number | 001-39817 |
| Entity Registrant Name | Boxed, Inc. |
| Entity Central Index Key | 0001828672 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 85-3316188 |
| Entity Address, Address Line One | 61 Broadway |
| Entity Address, Address Line Two | Floor 30 |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10006 |
| City Area Code | 646 |
| Local Phone Number | 586-5599 |
| Title of 12(b) Security | Common stock, $0.0001 par value per share |
| Trading Symbol | BOXD |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
