| Cover | Aug. 07, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Aug. 07, 2023 |
| Entity File Number | 000-20333 |
| Entity Registrant Name | NOCOPI TECHNOLOGIES, INC. |
| Entity Central Index Key | 0000888981 |
| Entity Tax Identification Number | 87-0406496 |
| Entity Incorporation, State or Country Code | MD |
| Entity Address, Address Line One | 480 Shoemaker Road |
| Entity Address, Address Line Two | Suite 104 |
| Entity Address, City or Town | King of Prussia |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19406 |
| City Area Code | (610) |
| Local Phone Number | 834-9600 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
