| Cover | May 13, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | May 13, 2024 |
| Entity File Number | 814-00235 |
| Entity Registrant Name | RAND CAPITAL CORPORATION |
| Entity Central Index Key | 0000081955 |
| Entity Tax Identification Number | 16-0961359 |
| Entity Incorporation, State or Country Code | NY |
| Entity Address, Address Line One | 1405 Rand Building |
| Entity Address, City or Town | Buffalo |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 14203 |
| City Area Code | (716) |
| Local Phone Number | 853-0802 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.10 par value |
| Trading Symbol | RAND |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Information, Former Legal or Registered Name | Not Applicable |
