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JWT Signer / Builder (HS256)

Sign JSON Web Tokens locally with HS256, HS384 or HS512.

Free · Runs in your browser · Last updated

About this tool

Build and sign JWTs in your browser using the Web Crypto API. Edit header and payload, choose algorithm and secret, get the signed token.

Privacy

All processing for JWT Builder happens locally inside your browser using JavaScript. Your input is never uploaded to a server, logged, or shared with third parties.

Frequently asked questions

Is the JWT Builder free to use?

Yes. JWT Builder is completely free for both personal and commercial projects. There are no usage limits, no sign-up, and no premium tier.

Is my data safe when I use JWT Builder?

All processing happens locally in your browser using JavaScript. Your input is never uploaded to our servers, logged, or shared with any third party.

Does JWT Builder work offline?

Once the page has loaded, the tool runs entirely client-side. You can disconnect from the internet and it will keep working in the same browser tab.

Which browsers are supported?

JWT Builder works in all modern browsers, including the latest versions of Chrome, Firefox, Safari, Edge, Brave, and Opera, on desktop and mobile.

Do I need to install anything?

No. JWT Builder runs in any modern web browser with no installation, browser extension, or account required.

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