JWT Validator: Verify Signatures and Claims Online

Decoding a JWT shows claims but does not prove authenticity. Production debugging needs signature verification and structured checks on time and audience claims.

The JWT Validator goes beyond the JWT Decoder:

1. HS256 — verify with your HMAC secret
2. RS256 — verify with an RSA public key PEM
3. Claims panel — exp, nbf, aud and iss with pass/fail badges

Typical workflow

• Paste a token from Authorization: Bearer …
• Enter the verifier (secret or public key)
• Optionally set expected aud and iss
• Read signature and claim results before trusting the payload

Build test tokens with the JWT Signer, then validate them here. Everything runs in the browser.

JWT Validator