HMAC Generator — free online tool

Sometimes you need to sign a message so the other side can check it really came from you and wasn't changed on the way. That usually means an HMAC, and writing a quick script just to get one signature is a hassle. We added a free tool that does it for you — HMAC Generator — right in your browser.

What it does

You paste a message and a secret key, pick a hash, and it gives you back the HMAC signature. You can choose SHA-256, SHA-1, SHA-384 or SHA-512, so it matches whatever the other system expects.

Nothing leaves your device

It all runs inside your browser. Your message and your secret key are never uploaded to a server, and nothing is saved anywhere. When you close the tab, it's gone.

How to use it

  1. Open HMAC Generator and type or paste your message.
  2. Enter your secret key and choose the hash you need (SHA-256, SHA-1, SHA-384 or SHA-512).
  3. Copy the signature it shows.

It's free with no limit. There are more small tools on the Apps page.

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