MAC Address Validator

Check whether a MAC address string is valid and learn exactly why it fails.

MAC address

ValidYes

ReasonValid MAC address.

How to read the result

A valid MAC has exactly 12 hex digits grouped as 6 pairs (colon/hyphen), Cisco xxxx.xxxx.xxxx, or 12 plain digits. Anything else fails on characters, length, or grouping.

Example

00:1B:44:11:3A:B7 → valid; 00:1B:44:11:3A → wrong length

FAQ

What counts as valid?

6 byte pairs with : or -, Cisco dotted xxxx.xxxx.xxxx, or 12 plain hex digits.

Why did mine fail?

The tool reports illegal characters, wrong hex-digit count, or bad grouping.