A MAC address is an identification code. It’s used to define physical devices in a network, so that the network knows exactly which devices it is in communication with. There are plenty of practical reasons to have MAC addresses. It helps prevent criminals from imitating devices they don’t actually have, and is useful in creating a number of network filters for protection or organization.
Typically a MAC address remains unchanged forever, defining a specific network interface card for as long as it lasts (that’s sort of the point). However, this ID code can be changed, and we’re going to discuss how – and why – to do it.
Let’s talk about spoofing
Changing your MAC address, especially when doing it frequently, is called spoofing. The word “spoofing” does have a negative connotation – after all, it makes it sound like you’re trying to fool someone. However, there are plenty of worthwhile reasons to change your MAC address. Many people do it for privacy. Switching MAC addresses regularly makes it very difficult for networks to track your device and how you are using it. If you are using time-out Wi-Fi that only gives you, say, an hour of free Wi-Fi access (some businesses, like airports, do this), you can keep getting free Wi-Fi by switching your address from time to time.
However, there are also some downsides to spoofing. The big one is that companies often have security filters in place that only allow certain employee devices to access their networks. If you spoof an address, the network will no longer recognize you. This is why it’s important to record your original MAC address before you change it! It’s also why spoofing a work device is often a bad idea – save this trick for your personal, non-BYOD computers if possible.
Changing the MAC address on Windows
Download a MAC address changer. We’re recommending that you start here, because this is a simple and very effective method. MAC address changers are software tools that you can download. When they are up and running, they show you everything you could want to know about all the network connections on your computer, including the original and active MAC addresses, and network speed. They include options to change MAC addresses and set certain rules for making the change random, making the change persistent, restoring original settings, and so on…all located on one pop-up window. It’s a fun little solution. We recommend using the Technitium Mac Address Changer, which has done a good job of keeping current with Windows 10.
(Optional) Change the address manually. If you really don’t want to download any new tools, there is a way to change the address manually on Windows. Head over to your Control Panel (you can find this by searching for it if you aren’t sure where it is), and look for the option that says Network Connections. This will show you all the connected devices you currently have on this network. Choose the one you want to change, right click it, and choose Properties. In the window that opens, go to the Advanced tab and click the Property option that says “Network Address” or “MAC Address” or something similar. This will bring up the address in the small Value box. You can click on this box and set the MAC code to anything you want.
Changing the MAC address on OS X
Check your MAC address. There are some address changers designed for OS X (MacSpoofer is one of the most notable), but the process to reset your address is so simple there probably isn’t much need for one if you only want to change once. First, you’ll want to check and record your MAC number. You see the Wi-Fi sign in the upper right corner of your OS X? Hold down the Option key and click the Wi-Fi button. The second line that appears in the drop-down menu should be your address – and it will say Address in gray letters so there’s no confusion.
Open a Terminal. You can find the Terminal app by going to Applications, choosing Utilities, and selecting Terminal. It’s type to type out a couple of commands!
Choose how to change your address. If you want to specify a new set of numbers – maybe you want an address that’s easy to remember – then use the Terminal and type in “sudo ifconfig en0 ether aa:bb:cc:dd:ee:ff” although replace the alphabet with the code you want. If this doesn’t work, trying using “en1” instead of “en0” in the command, which can account for some Ethernet ports. If you want to set a completely random number instead, type in (or maybe just paste), “openssl rand -hex 6 | sed ‘s/\(..\)/\1:/g; s/.$//’ | xargs sudo ifconfig en0 ether” and enter it. Again, if this doesn’t work try using “en1” instead of “en0.” A random address is usually better for privacy.
A couple notes
This isn’t always a clean process. Driver compatibility, syncing problems, network settings, and other issues may put up roadblocks. Sometimes, you’ll have to be patient, or switch to another device.
Also, you should restart your network after changing your MAC address to fully realize the effects. If you aren’t in a position to restart the Wi-Fi itself, then shut down the Wi-Fi on your device and restart it again for a similar sort of reboot.