Compute a keyed hash over a message with a shared secret, or verify an HMAC you were given. Built on the Web Crypto API with SHA-1 through SHA-512, hex output, and nothing leaving your browser.
Keyed integrityProves a message came from a holder of the secret.
Four hashesSHA-1, SHA-256, SHA-384 and SHA-512.
Verify modeCompare against an expected HMAC, constant time.
Local onlyKey and message stay in your browser.
What it does
GenerateHMAC of message under a key
VerifyMatch an expected HMAC
AlgorithmHMAC with your chosen hash
EncodingUTF-8 input, hex output
EngineBrowser Web Crypto
Needs HTTPS for Web Crypto. HMAC is for integrity and authenticity, not password storage.
HMACSHA-256SHA-512HexVerifyWeb Crypto
Message
The text to authenticate.
Secret key
Hash
Expected HMAC (hex)
UniCybers Labs • HMAC GeneratorRuns locally in your browser.
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