ToolVyne

JWT Generator

Enter a payload and secret to generate a signed HS256 JWT, useful for testing an API locally without a real auth server.

Payload (JSON)
Signed token

Only HS256 is supported here, since it's a shared-secret algorithm that can run entirely in your browser. RS256 and other asymmetric algorithms need a private key and aren't something you should generate in a public web tool. Everything above runs locally; your secret is never sent anywhere.

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Frequently asked questions

Why is only HS256 supported, not RS256?+

HS256 uses a shared secret, so signing can happen entirely in your browser. RS256 needs a private key, which isn't something a public web tool should be generating or handling; use a proper backend or CLI tool for that.

Is my secret sent anywhere?+

No, signing happens locally using the Web Crypto API. Nothing about the payload or secret leaves your browser.

Should I use tokens generated here in production?+

No, this is for local testing and debugging against a known secret, not for issuing real user tokens. A real auth system should generate and sign tokens server-side.

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