Generate cryptographic HMAC signatures with secret keys in hex and base64 formats in-browser.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Select SHA-256, SHA-384, or SHA-512.
Type or generate a secret key and paste the payload message.
Copy the calculated Hex or Base64 signature.
Yes, HMAC computation uses the local hardware W3C Web Crypto Subtle API with zero network requests.
Both hexadecimal and Base64 formatted string representations are generated simultaneously.
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