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HMAC generator

Sign text with an HMAC key and compare digests.

0 characters5M limit
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About HMAC generator

Compute a keyed message digest when you need to reproduce or inspect an HMAC calculation. Both the key bytes and the message bytes must match the values used by the other system.

Steps, and limitations

How to use it

  1. Choose the algorithm and the key and message encodings.
  2. Enter the key and message, then calculate the HMAC.
  3. Copy the digest or compare it with the expected signature.

Things to know

  • HMAC authenticates a message with a shared secret; it does not encrypt that message.
  • Different whitespace or encodings produce different bytes and therefore different digests. Do not paste production secrets on a device you do not trust.

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