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How to generate an HMAC signature
Create HMAC-SHA-256 (or SHA-384/SHA-512) signatures in your browser for webhooks and APIs.
HMAC vs a plain hash
A SHA hash only digests the message. HMAC also uses a secret key, which is what webhook providers expect when they say “sign the payload”.
Steps
1) Open HMAC Generator. 2) Choose HMAC-SHA-256 (typical). 3) Enter the secret and the message. 4) Click Run. Output is lowercase hex. The secret stays in this tab.