ToolToUse

Security & Password

JWT HMAC Signature Verifier

Verify that an HS256/HS384/HS512 JWT was signed with your secret.

RS256/ES256 and other public-key tokens can't be verified here.

Security & Password

JWT HMAC Signature Verifier

Local only
Everything stays in your browser

Your text is processed on your device — nothing is uploaded to a server.

How it works

Recomputes the HMAC over header.payload and compares it with the signature; also reports exp/nbf. Runs in your browser; nothing is uploaded. RS256/ES256 and other public-key tokens can't be verified here.

Good to know

Frequently asked questions

How do I use it?

Enter your jwt, adjust the options and press “Verify”. Check the result, then copy or download it.

How does it work?

Recomputes the HMAC over header.payload and compares it with the signature; also reports exp/nbf. Runs in your browser; nothing is uploaded.

Are there limitations?

RS256/ES256 and other public-key tokens can't be verified here.

Is my data uploaded?

No. Everything is processed in your browser and nothing is sent to a server. No account is needed.

Keep exploring

View all