UUID Studio

UUID Studio

JWT Generator

Sign test JWTs with HMAC-SHA256.

  • đź”’ No data stored or uploaded
  • ⚡ 100% client-side
  • 🆓 Free, no account
Click Convert when ready

Override only when Auto cannot parse your paste. Changing this loads a matching sample into Input — click Convert to run. Use Load sample to cycle every format example.

All conversions

Read-only representations of the same 16 bytes. Every textual form is listed here, not in “Prefer format”.

Paste two values: if both sides are valid JSON, a structural diff appears; otherwise UUID / bytes are compared when both decode to the same format.

A
B

Create or edit JSON here (syntax colors), then format, validate, or convert - same as MongoDB $binary UUID blobs on the Convert tab once detected.

New document

Hash, HMAC, AES-GCM/CBC + RSA-OAEP, codecs, JWT decoding, UUID v4, and secure random - all client-side. JWTs use Base64URL (three segments), not a single MIME Base64 block - use Decode JWT below, not raw Base64 decode.

Examples

  • Payload 
    {"sub":"user-1","iat":1516239022}
  • Secret 
    demo-secret

About JWT Generator

Testing an API that expects a JWT often means you need to mint one yourself first, without setting up a full auth server just to get a token to test against.

Paste a payload and a secret to sign an HS256 JWT locally - useful for local development, integration tests, and debugging auth middleware. This tool only supports HMAC (HS256); for RS256 or other asymmetric signing, use your backend framework's own signing flow. Never reuse these secrets for anything real.

FAQ

RS256?
This tool supports HS256; use your framework for asymmetric signing.