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JWT Generator

Create and sign JSON Web Tokens (JWT) online with HS256, HS384, or HS512. Edit the payload, set your secret, and get a valid signed token instantly. Free and 100% client-side.

Built & Maintained by the devtoolspack Team

Last updated: August 2026

Token appears here…

Generate Signed JWTs in Your Browser

This JWT generator builds and signs JSON Web Tokens using the Web Crypto API. Choose an HMAC algorithm (HS256, HS384, or HS512), edit the claims as JSON, provide your secret, and get a fully valid token that verifies on any server sharing that secret.

Perfect for Testing and Debugging

Quickly craft tokens with custom claims to test authentication flows, mock API requests, or learn how JWTs work. Pair it with our JWT Decoder to inspect the header, payload, and signature.

Private by Design

Your payload and secret never leave your browser — all signing happens locally. Use throwaway secrets for testing, and keep production token signing on your server.

Frequently Asked Questions

What signing algorithms are supported?

This generator creates HMAC-signed tokens: HS256, HS384, and HS512. These use a shared secret and are the most common choice for symmetric JWT signing.

Is the token cryptographically valid?

Yes. The signature is computed with the Web Crypto API (HMAC-SHA-256/384/512), so the resulting token verifies correctly on any server using the same secret. You can confirm it with our JWT Decoder.

What is the difference between HS256 and RS256?

HS256 (used here) signs with a single shared secret. RS256 uses an asymmetric private/public key pair. HMAC is simpler and ideal when the same party issues and verifies tokens.

Should I generate production tokens here?

This tool is for development, testing, and learning. Because signing requires your secret, only use non-sensitive or throwaway secrets — everything runs locally, but you should still sign real production tokens on your server.

Does my secret leave my browser?

No. The header, payload, and secret are all processed locally with the Web Crypto API. Nothing is sent to a server.

Cite this Tool

Using this tool for a technical blog, research, or documentation? Copy a pre-formatted citation below to link back to devtoolspack.

APA Citation
devtoolspack. (2026). JWT Generator. https://devtoolspack.dev/jwt-generator
MLA Citation
"JWT Generator." devtoolspack, 2026, https://devtoolspack.dev/jwt-generator.