Compute HMAC-MD5 from a message and shared secret key. HMAC-MD5 appears in older protocols and embedded systems even though MD5 alone is cryptographically broken for collisions.
How it works
HMAC-MD5 applies the HMAC construction with MD5 as the underlying hash, yielding a 32-character hex digest. The tool runs locally in your browser using crypto-js.
Common use cases
- Debugging legacy API signatures that still reference HMAC-MD5
- Teaching the difference between keyed HMAC and unkeyed MD5 hashes
- Verifying sample vectors from outdated documentation
Limitations
HMAC-MD5 must not be chosen for new systems—use HMAC-SHA256 instead. Secrets entered here are visible to anyone with access to your session. This authenticates messages; it does not encrypt them.
Example
Changing either the message or the secret changes the entire 128-bit digest expressed as 32 hex digits.