JWT Generator
Generate signed JWT tokens with custom payload and secret.
How to Use
- Edit the Payload JSON — add standard claims like sub, exp, iat, and any custom fields your application needs. The Header defaults to HS256 / JWT and can be edited to change the algorithm.
- Enter your HMAC secret in the Secret field. The token is deterministically signed — the same payload and secret always produce the same token. This is a signature, not random generation.
- Click Generate JWT and copy the resulting token. It can be verified at jwt.io or any JWT library using the same secret key.
Frequently Asked Questions
- Is the JWT output random?
- No — JWT is a deterministic cryptographic signature. The same payload and secret always produce the same token. Only claims you change manually (like iat — issued-at) will produce a different token.
- Is it safe to generate JWTs here?
- This tool runs entirely in your browser using the Web Crypto API — your secret and payload never leave your device. For production use, always generate JWTs server-side so the secret remains confidential and never appears in client code.
- Is data saved?
- No. Everything runs in your browser — no data is uploaded or stored.