JWT Decoder

Decode and inspect JSON Web Tokens (JWT) online for free. View header, payload, expiration times, and signature without sending tokens to any server.

Decode and inspect JSON Web Tokens (JWT) safely. View the decoded header, payload claims, expiration timestamps, and issuer information in formatted JSON. 100% private with no server storage.

How to use

  1. Paste an encoded JSON Web Token (JWT) string into the input field.
  2. The token header and payload claims are automatically parsed into syntax-highlighted JSON.
  3. Inspect the expiration status (exp), issued timestamp (iat), and algorithm signature.
  4. Copy either the header, payload, or full decoded object.

Frequently asked questions

Does decoding a JWT verify its cryptographic signature?

No. Decoding only reads the claims encoded in base64url. To verify signature authenticity, you must validate against the issuer secret or public key.

Is my secret token sent over the network?

Never. Decoding is 100% client-side via native browser JavaScript. Your token never leaves your device.

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