| Document and Entity Information | Oct. 20, 2023 |
| Document And Entity Information [Line Items] | |
| Amendment Flag | true |
| Entity Central Index Key | 0001662774 |
| Document Type | 8-K/A |
| Document Period End Date | Oct. 20, 2023 |
| Entity Registrant Name | Quince Therapeutics, Inc. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-38890 |
| Entity Tax Identification Number | 90-1024039 |
| Entity Address, Address Line One | 611 Gateway Boulevard |
| Entity Address, Address Line Two | Suite 273 |
| Entity Address, City or Town | South San Francisco |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94080 |
| City Area Code | (415) |
| Local Phone Number | 910-5717 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Amendment Description | On October 23, 2023, Quince Therapeutics, Inc. (the “Company”) filed a Current Report on Form 8-K (the “Original Form 8-K”) with the Securities and Exchange Commission (the “SEC”) to report the closing of the Company’s acquisition of EryDel S.p.A, a company with shares incorporated under the laws of Italy (“EryDel”), pursuant to that certain Stock Purchase Agreement, dated as of July 21, 2023, by and among the Company, EryDel, EryDel Italy, Inc., a Delaware corporation, holders of EryDel capital stock and the managers of EryDel (the “EryDel Shareholders”) and Shareholder Representative Services LLC, a Colorado limited liability company solely in its capacity as the representative, agent and attorney-in-fact of the EryDel Shareholders (the “Acquisition”). This Amendment No. 1 to the Current Report on Form 8-K/A (this “Amendment No. 1”) amends the Original Form 8-K to provide the historical financial statements of EryDel as required under Item 9.01(a) and the pro forma financial information required under Item 9.01(b) not later than 71 calendar days after the date that the Original Form 8-K was required to be filed with the SEC. The pro forma financial information included in this Amendment No. 1 gives effect to certain pro forma events related to the Acquisition and has been presented for informational purposes only. It does not purport to represent the actual results of operations the Company and EryDel would have achieved had the Company held the assets of EryDel during the periods presented in the pro forma financial information. Moreover, it does not represent or purport to represent the future financial position or operating results of the Company following the Acquisition. |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common Stock (par value $0.001 per share) |
| Trading Symbol | QNCX |
| Security Exchange Name | NASDAQ |
| Series A Preferred Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Series A Junior Participating Preferred Purchase Rights |
| Security Exchange Name | NASDAQ |
