JWT Decoder/Encoder

Decode and encode JSON Web Tokens (JWT) for debugging, development, and security testing. Paste a JWT or create a new one below.

🔐 JWT Decoder/Encoder Features

🧩 Decoding Features

  • Decode JWTs and view header, payload, and signature
  • Supports HS256, RS256 algorithms
  • Error detection & validation
  • Safe decoding process

✍️ Encoding Features

  • Encode new JWTs with custom payloads
  • Choose signing algorithm
  • One-click copy functionality
  • Input/output validation

🔒 Security

  • Works entirely in your browser
  • No data sent to server
  • Secure key handling

🚀 Use Cases & Applications

Web Development

Debug authentication flows and inspect JWTs in web apps.

API Testing

Generate and verify JWTs for API requests and responses.

Security Audits

Check JWT structure and claims for vulnerabilities.

💡 Pro Tip: Never share your secret keys. Always verify JWTs on the server side for security.