Networking – How to find the MAC address of a remote computer

networkingtcpip

I know the IP address of a host on my own LAN. Using that, how can I find its MAC address (without having to physically access it)?

Best Answer

If you are on a Windows machine, open a command box (Start...Run...cmd), ping the target machine so you have made contact with it, and then issue the command arp -a to view your local ARP table, which will list IP addresses and their corresponding MAC addresses, e.g.,

C:\Users\L3K> arp -a

Interface: 192.168.200.128 --- 0xb
  Internet Address      Physical Address      Type
  192.168.200.1         00-50-7f-c3-5c-88     dynamic
  192.168.200.2         00-50-7f-d1-e1-40     dynamic
  192.168.200.6         00-80-77-dd-a8-6b     dynamic

If you are on a Linux-based system, install the arp-scan utility, and then from a command line you can ask for a scan of your network - in my case:

sudo arp-scan 192.168.200.0/24

If you are using an interface other than Ethernet, say, wireless, you will need to specify that, such as

sudo arp-scan -I wlan0 192.168.200.0/24

If you don't know what interface you're using, simply use the appropriate command below.

ifconfig  (For Debian based OS such as Ubuntu)
ip link   (For OS like Arch Linux)