JWT Encoder
Build and sign a JSON Web Token for testing — choose the payload, algorithm and expiry — and see the colour-coded parts.
Result
Enter a payload and secret to create a token.
How to use this tool
- Edit the JSON payload and enter a secret.
- Choose the algorithm and an optional expiry, then select Create token.
How it works
The header and payload are Base64URL-encoded and joined with a dot; the signature is HMAC-SHA of that text with your secret, also Base64URL-encoded (RFC 7519).
Example
The jwt.io example
Payload {"sub":"1234567890","name":"John Doe","iat":1516239022} with secret your-256-bit-secret gives the signature SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c.
Privacy and limitations
- Everything runs in your browser; nothing you enter is uploaded or stored.
- For testing and development. Keep production secrets on your server.
Frequently asked questions
Is the payload encrypted?
No — anyone can decode it. Never put secrets in a JWT payload.
Can I check a token?
Yes, with the JWT Decoder.