Security Tools

HMAC Generator

Enter a message and secret key to compute an HMAC, entirely in your browser using the Web Crypto API.

HMAC (SHA-256)

Computed entirely in your browser via the Web Crypto API — your message and secret are never sent anywhere.

How to use this tool

  1. 1Enter your message.
  2. 2Enter your secret key.
  3. 3Choose a hash algorithm.
  4. 4See the resulting HMAC in hex.

Frequently asked questions

How is this different from a plain hash?+

A plain hash (like the file checksum tool) has no secret key, so anyone can recompute it — an HMAC mixes in a secret key, so only someone who knows the key can produce or verify a matching HMAC.

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