JWS Sign & Verify
Sign & verify any payload as a compact JSON Web Signature. This tool does both sign and verify on one page — pick a mode, paste your data, and click. Everything runs on your device, nothing is sent to a server.
Everything runs in your browser. Your data is never sent to our servers.
Example
Example Input
hello world
Example Output
eyJ…(compact JWS)
How to Use
- 1Choose Sign or Verify mode at the top.
- 2Fill the Input field and, if required, complete the fields in "More settings" (key/password).
- 3Click the button (or press Ctrl+Enter) to process.
- 4Copy the result with the Copy button.
About JWS
JSON Web Signature (JWS) is the standard underlying JWT signatures, but its payload can be any data (not just JSON claims). The result is a compact header.payload.signature token.
Use Sign mode to sign your text, and Verify to check the authenticity of a received JWS. Supports HS256 (secret) plus RS256/ES256 (PEM keys).
JWS is useful for guaranteeing message integrity between services without the JWT claim framework. For standard auth tokens, use JWT.
FAQ
Are my data or keys sent to a server?
No. JWS runs entirely in your browser using the Web Crypto API and client-side libraries. Your data, passwords, and keys never leave your device.