JSONBrew

JWT Decoder & Verifier

Decode, inspect, and verify JSON Web Tokens instantly in your browser.

How to Use JWT Decoder & Verifier

  1. Paste your JWT token into the input field, or click Sample to load an example.
  2. The decoded header and payload appear instantly below, with expiration status.
  3. Switch to Verify mode and enter a secret key to validate the signature.

Features

  • Instant decoding of JWT header, payload, and signature.
  • Color-coded token visualization (header, payload, signature).
  • Expiration check with clear valid/expired status indicator.
  • Optional signature verification with secret key input.
  • 100% client-side — your data never leaves your browser.