JWT decoder and local signature check

Decode a JWT, or check its signature with an RSA public key.

Local signature check (optional, advanced)

Paste only an RSA public JWK/JWKS from a key set you already intend to use. This page does not fetch jku, x5u, or jwks_uri, try HS secrets, issue tokens, or decrypt JWE.

Without a pasted public key, this page only decodes the Header and Payload. A local signature match only means the compact JWS signature matched the selected public key; it does not prove application authorization or business trust. Your server still has to validate expected iss, aud, exp, nbf, scope, roles, nonce, jti, and policy.

ResultWaiting for token
Algorithm
kid
Expires
Full Header (local debug)
···
Full Payload (local debug, may contain PII or authorization context)
···
Local debug summary
Redacted collaboration report