QuackyardJWT Encoder
Sign a JSON Web Token with HMAC — edit the header and the claims, pick HS256, HS384 or HS512.
A JSON object naming the algorithm. It's signed as it stands, with the "alg" of the algorithm chosen below.
The claims to sign, as a JSON object. The registered ones — iss, sub, aud, iat, nbf, exp — are explained below.
The secret never leaves your browser: the signature is worked out here, in the page, and nothing is sent anywhere. In real use a server signs the token and keeps the secret, because anyone who holds it can make tokens that pass for yours.
Algorithm
A life stamps iat from your clock and exp that far ahead. The payload keeps any iat it already carries.
The token
ewogICJhbGciOiAiSFMyNTYiLAogICJ0eXAiOiAiSldUIgp9.ewogICJpc3MiOiAiaHR0cHM6Ly9xdWFja3lhcmQuY29tIiwKICAic3ViIjogInVzZXJfMTIzNDUiLAogICJuYW1lIjogIkFkYSBMb3ZlbGFjZSIKfQ.Y_E9Mt8VjyxwbydOqgcsiC6xNe6YWRMP0L39nsjFJXg
headerpayloadsignature
19 bytes of secret, signed as HS256. HMAC with SHA: one shared secret makes the signature and checks it, so anyone who can check this token can also forge it.
Claims
| Claim | In this token |
|---|---|
| iss Issuer is who created the token, usually a URL or a domain name | https://quackyard.com |
| sub Subject is who the token is about, usually a user id | user_12345 |
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