◇Free
HMAC-SHA256 generator
Compute a keyed SHA-256 authenticator using a local UTF-8 key.
Compute a keyed SHA-256 authenticator using a local UTF-8 key. Generate a hexadecimal message authenticator from supplied text and a nonempty secret key. Both the key and message are interpreted as UTF-8 bytes by the browser cryptography API.
How to use
- Enter your text, values, or image.
- Adjust the options and run the tool.
- Copy or download your result.
Worked example
Example input
Input: The quick brown fox jumps over the lazy dog Secret key (local only): key
Example result
f7bc83f430538424b13298e6aa6fb143ef4d59a14946175997479dbc2d1a3cd8
Limitations and details
This signs text only and does not verify received MACs; a hex-looking key is treated as literal UTF-8 text, not decoded key bytes.
Inputs and options
- Input
- Text
- Secret key (local only)
- Text
Frequently asked questions
Is this tool free and private?
Yes. All 300 tools are free in this phase. Processing happens in your browser; your input and files are not sent to our servers.