
What is TLS fingerprinting? How JA3 and JA4 identify a client
TLS fingerprinting identifies the software behind a connection from its TLS handshake. How it works, what JA3 and JA4 are, and what it reveals.
Blog / Network signals

TLS fingerprinting identifies the software behind a connection from its TLS handshake. How it works, what JA3 and JA4 are, and what it reveals.

What IP reputation is, how the 0 to 100 score is built, and why a clean IP score alone will not catch fraud. The lagging, shared, and recycled-IP problem.

What JA4 fingerprinting is, how it fixes JA3's weakness to TLS randomization, the JA4 string format and JA4+ suite, and what it can and cannot identify.

How to detect VPNs in 2026: the methods that actually work, why an IP check alone fails, and how masked traffic ties to abuse and risk.

How proxy detection works for fraud prevention: 13 techniques, why residential proxies are hard to spot, and why an IP check alone is never enough.