JWT Debugger

Decode JWT headers, claims, and expiration windows at a glance

Paste a JWT and inspect the header, payload, and time claims (exp, iat, nbf) in your local time. A quick way to diagnose auth issues against local or staging APIs.

Common findings

  • exp is past but the server still accepts the token
  • iss or aud differ from expected values
  • alg is `none` or unexpected
  • payload includes unexpected scope claims (`scope`, `scp`, `roles`)

Security notes

This tool does not verify signatures. Always validate the signature separately with the proper key before trusting the claims. And avoid leaving decoded tokens in chat threads or public repos.

Pairs well with

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JSON Formatter

Format sample payloads before sending them back into the converter.