JWT Encoder
Build and sign a JWT with HS256/384/512 from a header, payload, and secret.
Header + Payload
Signed token
About the JWT Encoder
Craft a JSON Web Token by editing the payload JSON, choosing an HMAC algorithm, and providing a secret. The token is signed locally using the Web Crypto API, with quick-add buttons for common iat/exp claims.
Examples
Sign a payload
{"sub":"1234567890"}Output
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...Related tools
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Frequently asked questions
Version 1.0.0 · Updated 2026-08-10 · Runs entirely in your browser