JWT Generator
Generate and decode JWTs online, with signing, decoding, and verification right in your browser.
Local browser processing
No sign-up required
Supports signature verification
GeneratorGenerate and decode JWTs based on HMAC (HS256/384/512)
Algorithm
Header (auto-generated from algorithm)
{
"alg": "HS256",
"typ": "JWT"
}Payload
Generated JWT
Generating…
Supports HMAC algorithms only (HS256 / HS384 / HS512)Computed locally in browser · no data uploaded
How It WorksJWT
Overview
Generate or decode JWTs using the browser's built-in SubtleCrypto. In encode mode, edit the payload, pick HS256/HS384/HS512, and enter a secret to sign a standard JWT. In decode mode, paste an existing JWT to inspect its header, payload, and time claims like exp/iat, and optionally enter a secret to verify the signature. Everything runs locally in your browser; your data never leaves your device.
Use Cases
Test a JWT-based login / auth flow locallyCheck the content and expiry of a JWT issued by a third partyDebug an "invalid token" issue by verifying whether the signature matchesLearn the structure of a JWT (header / payload / signature)
Steps
123
Choose encode or decodeSet the algorithm and secretCopy or verify