Compute an HMAC (keyed-hash message authentication code) for text using a secret key, entirely in your browser.
An HMAC proves that a message was created by someone who holds a shared secret key, and that the message hasn't been altered — unlike a plain hash, it can't be recomputed without the key. Computed with the browser's native SubtleCrypto.sign('HMAC', ...); nothing you type is ever sent to a server.
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HMAC Generator computes Hash-based Message Authentication Codes (HMAC) using secret keys and cryptographic hash algorithms like SHA-256.
Message: payload Key: secret123 HMAC-SHA256: 86b3e77f0c13e5e5f3099d0a645ef59a22f71887376c96e38202157053e1f5a5
No. HMAC computation is executed locally inside your browser using Web Crypto APIs.
Yes. You can switch signature output formatting between hex and Base64.