| Document and Entity Information | Nov. 09, 2020 |
| Document and Entity Information [Abstract] | |
| Entity Central Index Key | 0001603454 |
| Amendment Flag | false |
| Document Type | 8-K |
| Document Period End Date | Nov. 9, 2020 |
| Entity Registrant Name | Celcuity Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-38207 |
| Entity Tax Identification Number | 82-2863566 |
| Entity Address, Address Line One | 16305 36th Avenue North |
| Entity Address, Address Line Two | Suite 100 |
| Entity Address, City or Town | Minneapolis |
| Entity Address, State or Province | MN |
| Entity Address, Postal Zip Code | 55446 |
| City Area Code | 763 |
| Local Phone Number | 392-0767 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.001 par value per share |
| Trading Symbol | CELC |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | true |
