| Cover | Jun. 18, 2024 |
| Entity Addresses [Line Items] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | This Amendment No. 1 to Form 8-K of Atlantic International Corp. filed with the Securities and Exchange Commission on June 25, 2025 is being filed to provide the following exhibits: |
| Document Period End Date | Jun. 18, 2024 |
| Entity File Number | 001-40760 |
| Entity Registrant Name | ATLANTIC INTERNATIONAL CORP. |
| Entity Central Index Key | 0001605888 |
| Entity Tax Identification Number | 46-5319744 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 270 Sylvan Avenue |
| Entity Address, Address Line Two | Suite 2230 |
| Entity Address, City or Town | Englewood Cliffs |
| Entity Address, State or Province | NJ |
| Entity Address, Postal Zip Code | 07632 |
| City Area Code | 201 |
| Local Phone Number | 899-4470 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | true |
| Entity Information, Former Legal or Registered Name | SeqLL Inc. |
| Former Address [Member] | |
| Entity Addresses [Line Items] | |
| Entity Address, Address Line One | 3 Federal Street |
| Entity Address, City or Town | Billerica |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 01821 |
