Generate SHA-256, SHA-512, SHA-384, and SHA-1 HMAC signatures.
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.
Input your secret HMAC key and the payload text or payload string.
Choose SHA-256, SHA-384, SHA-512, or SHA-1.
Copy the computed HMAC authentication code in Hexadecimal or Base64 encoding.
HMAC provides cryptographic message authentication and integrity verification for webhooks, API signatures, and token signing.
It executes in sub-millisecond time via the browser's native Web Crypto API.
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