HMAC Generator
Generate HMAC signatures with a secret key (SHA-256, SHA-512 and more).
HMAC combines a hash function with a secret key to prove that a message is authentic and unmodified.
About HMAC Generator
Compute an HMAC of a message with your own secret key using MD5, SHA-1, SHA-256, SHA-384 or SHA-512. HMACs are used to sign webhooks and API requests so the receiver can verify the message wasn't tampered with. Your key and message stay in your browser.
HMAC combines a hash function with a secret key to prove that a message is authentic and unmodified. It's how webhooks from payment providers and many APIs sign their requests. This HMAC generator computes the signature for a message and key using MD5, SHA-1, SHA-256, SHA-384 or SHA-512, entirely in your browser.
How to use HMAC Generator
- Enter your secret key.
- Choose the HMAC algorithm, typically SHA-256.
- Paste the message or request body to sign.
- Copy the resulting hexadecimal signature.
Key features
- HMAC with five hash algorithms.
- Instant results as you type.
- Copy-ready hex output.
- Key and message never leave your device.
Common use cases
- Testing a webhook signature check against a known payload.
- Signing API requests during development.
- Learning how keyed hashing differs from plain hashing.
Frequently asked questions
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