Cover - shares	3 Months Ended
	Mar. 31, 2024	Apr. 30, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-736297
Entity Registrant Name	Astera Labs, Inc.
Entity Incorporation State Country Code	DE
Entity Tax Identification Number	82-3437062
Entity Address, Address Line One	2901 Tasman Drive
Entity Address, Address Line Two	Suite 205
Entity Address City Or Town	Santa Clara
Entity Address State Or Province	CA
Entity Address Postal Zip Code	95054
City Area Code	(408)
Local Phone Number	337-9056
Security 12b Title	Common Stock, par value $0.0001 per share
Trading Symbol	ALAB
Security Exchange Name	NASDAQ
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		155,701,301
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001736297
Current Fiscal Year End Date	--12-31