HMAC Generator
Generate SHA-256, SHA-384, or SHA-512 message authentication codes locally.
Processing stays in your browser. Use test keys when debugging shared examples. No key or message is saved by this tool.
How to use the hmac generator
Enter a message, secret key, key encoding, and SHA algorithm to generate an HMAC. Messages use UTF-8; keys can use UTF-8 text or hexadecimal bytes. Results are available as hexadecimal and Base64.
Example
Use a test key and a sample request body to compare this result with your application's HMAC-SHA-256 output. Every space and newline in the message matters.
Good to know
HMAC authenticates bytes using a shared secret; it does not encrypt the message. Use the exact encoding and canonicalization required by your API. Processing stays local and requires HTTPS or localhost.