| Cover Page | Aug. 03, 2023 | Nov. 03, 2022 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Document Period End Date | Aug. 03, 2023 | |
| Entity Registrant Name | DERMTECH, INC. | |
| Entity Incorporation, State or Country Code | DE | |
| Entity File Number | 001-38118 | |
| Entity Tax Identification Number | 84-2870849 | |
| Entity Address, Address Line One | 12340 El Camino Real | |
| Entity Address, City or Town | San Diego | |
| Entity Address, State or Province | CA | |
| Entity Address, Postal Zip Code | 92130 | |
| City Area Code | 858 | |
| Local Phone Number | 450-4222 | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Title of 12(b) Security | Common Stock,par value $0.0001 per share | |
| Trading Symbol | DMTK | |
| Security Exchange Name | NASDAQ | |
| Entity Emerging Growth Company | false | |
| Amendment Flag | false | |
| Entity Central Index Key | 0001651944 |
