| Cover | Mar. 17, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Mar. 17, 2023 |
| Entity File Number | 001-14468 |
| Entity Registrant Name | PURE BIOSCIENCE, INC. |
| Entity Central Index Key | 0001006028 |
| Entity Tax Identification Number | 33-0530289 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 9669 Hermosa Avenue |
| Entity Address, City or Town | Rancho Cucamonga |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 91730 |
| City Area Code | (619) |
| Local Phone Number | 596-8600 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Information, Former Legal or Registered Name | Not applicable |
