JWT Generator
Generate signed JWT tokens with HMAC algorithms (HS256, HS384, HS512). Edit header and payload JSON, auto-fill common claims, all processed client-side.
How to Use the JWT Generator
- Select the signing algorithm (HS256, HS384, HS512).
- Enter your signing secret.
- Edit the header JSON (algorithm is auto-synced).
- Edit the payload JSON or use quick-add buttons for common claims (iat, exp, nbf, iss, sub).
- Click 'Generate JWT' to produce the signed token.
- Copy the generated JWT, displayed with color-coded header, payload, and signature.
About JWT Generator
JSON Web Tokens (JWTs) are a compact, URL-safe means of representing claims between two parties. A JWT consists of three Base64URL-encoded parts: a header (algorithm and type), a payload (claims), and a signature. This tool creates HMAC-signed JWTs using the Web Crypto API entirely in your browser. It supports HS256, HS384, and HS512 algorithms. Common claims like iat (issued at), exp (expiration), and sub (subject) can be auto-filled. This complements the JWT Decoder tool for full JWT development and testing workflow.
Frequently Asked Questions
HMAC (symmetric) algorithms can be fully implemented in the browser using the Web Crypto API. RSA and EC (asymmetric) algorithms require key pair management which is more complex for a browser-based tool.
This tool is designed for development and testing. For production, use established libraries in your application that properly handle key management, token validation, and security best practices.