JWT Generator & Verifier
Generate signed JSON Web Tokens with a custom payload and secret key (HS256/384/512). Verify existing tokens and decode their claims — all in your browser.
All signing and verification happens in your browser. Your secret key is never transmitted.
JWT Structure
A JWT consists of three Base64URL-encoded parts separated by dots: Header.Payload.Signature.
Standard Claims
| Claim | Description |
|---|---|
| iss | Issuer — who issued the token |
| sub | Subject — who the token represents |
| aud | Audience — intended recipient |
| exp | Expiration — Unix timestamp |
| iat | Issued At — when the token was created |
| nbf | Not Before — token not valid before this time |
| jti | JWT ID — unique identifier for the token |