How To Change Your MAC Address

A MAC address (which is short for medium access control address) is the unique identifier assigned to pretty much every network interface controller. The ethernet jack and the wifi adapter on your computer each have their own MAC address.

On networks (such as your home network, or the wifi network at Starbucks) the MAC address is typically used by the network to identify and track individual machines. This means that your machine can be tracked not only every time it logs in to the same network, but it can be tracked across other networks as well. You can hinder this by changing your MAC address, or configuring it to use a random MAC.

There are more than just privacy benefits to changing your MAC address. Some networks which provide only a limited amount of free access for guests, can have the timer reset if you disconnect, clear your browser cookies/cache, and reconnect with a new MAC. This can get you around bans on some services as well.

MAC addresses are typically burned into the firmware of the network controller from the factory. In the past, this sometimes made them very hard to change, but this is less of a problem with modern operating systems.

Scroll down for instructions for your particular system.

Most of you using Linux will likely have NetworkManager installed already. To set-and-forget your machine to automatically generate & provide a random MAC address every time you connect to a network, save the following file to /etc/NetworkManager/conf.d/:

random-mac.conf

##############################################################
## RANDOM MAC DROP-IN CONFIGURATION FILE FOR NETWORKMANAGER ##
## PROVIDED BY THE ANONYMOUS MILITARY INSTITUTE             ##
## HTTPS://BESTPOINT.INSTITUTE/DIY/CHANGE-MAC               ##
##############################################################
 
[device-mac-randomization]
# "yes" is already the default for scanning, but set it anyways.
wifi.scan-rand-mac-address=yes
 
[connection-mac-randomization]
# Randomize MAC for every ethernet connection.
ethernet.cloned-mac-address=random
# Generate a random MAC for each WiFi connection.
wifi.cloned-mac-address=random

Then reboot, or reset NetworkManager:

$ sudo service NetworkManager restart

If you are using iwd and its built-in network configuration without NetworkManager, set the following two lines under 'General' in /etc/iwd/main.conf:

[General]
AddressRandomization=once
AddressRandomizationRange=full

Before NetworkManager had flawless MAC randomization built in, the preferred Linux utility was GNU MAC Changer. You can find it at alobbs/macchanger, or for most Debian-based systems with apt install macchanger.