Free tool

JWT Verifier

Verify JWT signatures with HMAC secrets or RSA public keys.

JWT token

Secret or PEM public key (SPKI)HS fallback

Used only when the token header has no HS alg. PEM keys use the header alg (RS*/PS*/ES*).

Supports HS256/384/512 with a shared secret, and RS*/PS*/ES* with a PEM SPKI public key. Algorithm is taken from the JWT header. Verification runs locally in your browser.