HMAC Generator
Compute HMAC-SHA-1, SHA-256, SHA-384, or SHA-512 of any message with a secret key. Live computation as you type. Uses the browser's Web Crypto API.
HMAC (Hash-based Message Authentication Code) signs a message with a secret key so the recipient can verify both authenticity and integrity. It’s the building block behind webhook signatures (Stripe, GitHub), AWS request signing, and JWT’s HS256/HS384/HS512.
Type or paste a message and a secret key, pick an underlying hash, and the hex-encoded HMAC is computed instantly. Switch between HMAC-SHA-1, SHA-256, SHA-384, and SHA-512 to match whichever specification you’re verifying against. Computation uses crypto.subtle.sign — both the message and the key stay entirely on your device.