// network
what is JA3 TLS ClientHello fingerprint?
JA3 is an MD5 hash over the TLS ClientHello (version, cipher-suite list, extensions, elliptic curves, EC point formats). It is a server-side signal a browser page structurally cannot observe about itself; ab captures it per egress and feeds it to the tls layer.. Deprecated in favour of JA4 but still enforced by legacy WAFs. curl-impersonate deliberately mimics a Chrome ClientHello so its JA3 blends with real browsers.
source capture as of 2026-06-14
in the benchmark
JA3 TLS ClientHello fingerprint is tracked as part of the network taxonomy. see how tracked tools score against it on the capability matrix.