Skip to content
Convertto

HMAC Generator

Generate an HMAC signature with SHA-256, SHA-1, SHA-384 or SHA-512 and a secret key.

To generate an HMAC, enter your message and secret key and pick a hash algorithm. HMAC proves both integrity and authenticity because only someone holding the key can produce a matching signature — which is how webhook payloads from Stripe, GitHub and Slack are verified.

Runs in your browser
Privacy
Runs entirely in your browser — nothing is uploaded
Cost
Free, unlimited, no sign-up

Frequently asked questions

What is HMAC used for?

Verifying that a message came from someone holding a shared secret and was not altered. Webhook providers sign each payload with HMAC so the receiver can confirm it is genuine.

Is my secret key safe here?

The key is used only inside your browser via WebCrypto and is never sent anywhere. Even so, avoid pasting production secrets into any website as a matter of habit.

How to use the hmac generator

  1. 1Enter or paste your message.
  2. 2Enter or paste your secret key.
  3. 3Choose the algorithm.
  4. 4Choose the output.
  5. 5The result appears immediately — copy or download it.

Embed this tool

Put the working hmac generator on your own site. It runs in your visitors' browsers exactly as it does here — free, no account, nothing uploaded.

Share this tool

Related tools

JWT VerifierVerify a JWT's HS256 signature and its expiry, issuer and audience claims, entirely in your browser.Nano ID GeneratorGenerate compact URL-safe unique IDs — shorter than a UUID with comparable collision safety.Random String GeneratorGenerate random strings from a chosen character set — for keys, tokens and test data.UUID v4 GeneratorGenerate random RFC 4122 version 4 UUIDs in bulk.UUID v7 GeneratorGenerate time-sortable UUID version 7 identifiers — ideal as database primary keys.JWT SignerCreate a signed HS256, HS384 or HS512 JSON Web Token for testing, entirely in your browser.

Last updated

More hash & crypto tools