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JWT Decoder

Decode and verify JWT tokens instantly. View header, payload, and signature. Check token expiration. Free online JWT decoder for developers.

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📖 About this tool

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What is JWT Decoder?

JSON Web Tokens (JWT) are widely used for authentication and information exchange in web applications. Our JWT Decoder lets you inspect the contents of any JWT, view the header and payload, and verify the signature. Debug your tokens and understand what data they contain.

The tool runs entirely in your browser with no server-side processing. Your data never leaves your device, ensuring complete privacy and security. No registration required - just open and use.

How to use

  1. 1 Paste your JWT token in the input field
  2. 2 View decoded header, payload, and signature instantly
  3. 3 Inspect claims in the payload: iss, exp, sub, etc.
  4. 4 Validate token signature and structure
  5. 5 Copy decoded JSON or individual claims to clipboard

Common use cases

  • Debug authentication issues in web applications
  • Inspect access tokens and ID tokens from OAuth providers
  • Verify token claims before accepting them in your code

View full documentation for more use cases →