Ethernet MAC address on Macbook 12"
MacBook Retina 12" dont have Ethernet port built-in hence en0 is your wifi. Do you use any kind of adapter for ethernet to work? If so, you can use System Preferences &gt; Network &gt; (choose interface matched with your ethernet adapter) &gt; Advanced... &gt; Hardware. From here you can see your MAC Address easily if your ethernet adapter plugged :)