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Security

HMAC Generator

Compute HMAC signatures of a message with a secret key to test webhooks and API authentication.

  • Runs in your browser
  • Instant results
  • Free, no sign-up
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How to use the HMAC Generator

  1. Paste the message, such as a webhook body.
  2. Enter the secret key and its format.
  3. Compare the signatures with the one you received.

Frequently asked questions

What is HMAC?

A signature made from a message and a secret key. Only someone with the key can produce or check it.

Why doesn't my webhook signature match?

The body must be byte-for-byte identical, including whitespace, and some services sign a timestamp too.

Is SHA-1 HMAC still safe?

HMAC-SHA1 is still considered secure, but prefer HMAC-SHA256 for new systems.

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