Decode JWT Tokens Instantly

For developers and security testers who need to quickly inspect JWT header, payload, and signature. Paste your token and get a clear, structured view to debug authentication issues.

Open the Tool

Why use JWT Decoder?

Instantly decode header and payload JSON

Automatically detect and display signature presence

Check token expiration and validity

No data leaves your browser - fully client-side

Supports all JWT formats (HS256, RS256, etc.)

How it works

  1. Copy your JWT token from your application or request header.
  2. Paste the token into the input field above.
  3. Click the 'Decode JWT' button to see the decoded header and payload.
  4. Review the JSON output and signature information for debugging.

FAQ

What is a JWT token?

JWT (JSON Web Token) is an open standard for securely transmitting information between parties as a JSON object. It consists of three parts: header, payload, and signature.

Can I verify the signature with this tool?

This tool decodes the token and shows the signature part, but it does not verify cryptographic signatures. For verification, you need the secret key or public key.

Is my token data safe?

Yes, all decoding happens entirely in your browser. Your token is never sent to any server, ensuring complete privacy.

What if my token is invalid?

If the token is malformed or missing parts, the tool will display an error message indicating the issue, helping you identify problems.