| Cover | Jun. 23, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jun. 23, 2024 |
| Entity Registrant Name | Astera Labs, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-736297 |
| 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 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.0001 per share |
| Trading Symbol | ALAB |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001736297 |
