COVER - shares	6 Months Ended
	Jun. 30, 2025	Aug. 05, 2025
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2025
Document Transition Report	false
Entity File Number	001-38890
Entity Registrant Name	Quince Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
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
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	QNCX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		53,713,798
Entity Central Index Key	0001662774
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	Q2
Amendment Flag	false
Current Fiscal Year End Date	--12-31