regex for mac address

^[a-fA-F0-9]{2}(:[a-fA-F0-9]{2}){5}$

01:02:03:04:ab:cd definitely:not:a:mac 01-02-03-04-ab-cd

A simple expression to match an ethernet MAC address

A media access control address is a unique identifier assigned to a network interface controller for use as a network address within a network.

The expression is a 6 byte hexadecimal which is separated by colon (:) or a dash (-).

Cheatsheet

expr	usage
`/[a-zA-Z0-9]/`	matches all lowercase, uppercase letters and numbers
`/(hello){4}/`	matches "hellohellohellohello"

iHateRegex

by geon