About CMAC
CMAC is a block-cipher based message authentication code algorithm. RFC4493 defines AES-CMAC that uses AES encryption with a 128-bit key. NIST SP 800-38B suggests usages of AES with other key lengths and Triple DES.
Input: binary bytes (text input uses UTF-8; a file retains its original bytes). Output: text.
Format reference: CMAC background and specification
Example
Use “Try example” to load this public sample and its settings, then run it.
Settings used in this example
| Parameter | Example value | Input and choices |
|---|---|---|
| Key | {"option":"Hex","string":"2b7e151628aed2a6abf7158809cf4f3c"} | Key/text encoding: Hex, UTF8, Latin1, Base64 |
| Encryption algorithm | AES | AES, Triple DES |
Sample keys and passwords are public. Never use them to protect real data.
Result
070a16b46b4d4144f79bdd9dd04a287c
Parameters
| Parameter | Default value | Input and choices |
|---|---|---|
| Key | {"option":"Hex","string":""} | Key/text encoding: Hex, UTF8, Latin1, Base64 |
| Encryption algorithm | AES | AES, Triple DES |
Before interpreting the result
Use a checksum to compare exact bytes against a trusted digest. Choose a password hashing function for passwords and a MAC for keyed authentication. MD5 and SHA-1 are unsuitable for new security-sensitive designs.
How to use this page
- Paste your input or open a local file.
- Adjust tool options if needed, then choose Run tool.
- Copy the result or download the original output bytes.
Inputs and results are not added to the public catalogue or saved in the URL. Processing happens in your browser; HTTP Request and DNS over HTTPS send the requests you explicitly run. Files up to 128 MiB can be opened; decompression and image tools may have smaller processing limits. Large results have a shortened preview. Text and HTML downloads use UTF-8; binary downloads preserve output bytes. Pasted text follows browser newline handling; open a file when exact input bytes matter.