HMAC Generator
Generate HMAC authentication codes
How to Use
Enter message
Type or paste the message to authenticate.
Enter secret key
Input your secret key for the HMAC calculation.
Select algorithm
Choose HMAC-SHA256 (recommended) or another algorithm.
Copy HMAC
Copy the generated HMAC for API authentication or verification.
Frequently Asked Questions
What is HMAC?
HMAC (Hash-based Message Authentication Code) combines a secret key with a hash function to verify both data integrity and authenticity. It proves who sent a message.
How is HMAC different from a regular hash?
Regular hashes verify data hasn't changed. HMAC also verifies the sender, since only someone with the secret key could generate the correct HMAC.
What is HMAC used for?
API authentication, webhook verification, JWT signatures, message integrity in protocols, and anywhere you need to verify both content and sender.
Which algorithm should I use?
HMAC-SHA256 is the most common and recommended choice. HMAC-SHA512 offers more security for sensitive applications.
Is my secret key safe?
All processing happens locally in your browser. Your secret key never leaves your device or is transmitted anywhere.