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Free Online Tool

JWT Inspector

Free online JWT decoder and inspector for token headers, claims, and expiry debugging in authentication workflows.

Inspect JWT Claims

What problem does this tool solve?

Auth failures are difficult to debug when JWT claims are unreadable or validation context is missing.

How to use JWT Inspector

  1. Paste a JWT token from request headers or logs.
  2. Decode header and payload to inspect algorithm and claim values.
  3. Check exp, iat, iss, and aud against expected authentication settings.

FAQ: JWT Inspector

Does JWT Inspector verify token signatures?

No. It decodes claims for debugging. Signature verification must be done with the correct secret or public key.

Why does my token look valid but authentication still fails?

Common causes include issuer mismatch, audience mismatch, key rotation, or server clock drift.

Is browser-based JWT inspection safer for debugging?

Local inspection reduces exposure risk compared with sending tokens to external services.