Developer Utilities

JWT Decoder

Decode JWT tokens and inspect header, payload and signature.

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Paste JWT Token to decode

JWT consists of three parts: Header.Payload.Signature

What is JWT Decoder?

JWT (JSON Web Token) is a standard for secure information transmission. This tool decodes JWT tokens to view their contents.

JWT Structure

  • Header: Algorithm and token type
  • Payload: Claims and data
  • Signature: Verification signature

Use Cases

  • API debugging
  • Authentication troubleshooting
  • Token inspection

Frequently Asked Questions

Does decoding a JWT verify it?
No. Decoding is just Base64URL plus JSON parsing — anyone can read the payload. Verification requires checking the signature with the key and validating claims such as exp, nbf, iss, and aud. Never trust a decoded-but-unverified token.
Is it safe to paste my token here?
Decoding runs entirely in your browser; the token is not uploaded. Keep in mind that a JWT payload is encoded, not encrypted — anyone holding the token can read it the same way, so treat JWTs like credentials.
Why does my token show as invalid or expired?
The usual reasons: exp has passed, the clock skew between client and server is too large, or aud/iss do not match what your backend expects. Decode the payload and compare each claim against the server configuration.