How to change the MAC Address on OS X

In case if you don't already know, a MAC (Media Access Control) address is an identifier (basicallyÐ± a series of numbers and letters) that is automatically assigned to a network card so that your computer can be recognized in a network. Even if it is recommended not to change your MAC address, there may be some situations where you will have to. So, if you want to change (or spoof) your MAC address, and you don't know how, then continue reading this guide.

Finding your MAC address

First of all, before starting to change your MAC address, you might want to know how to find it, in case if you want to write it down or for any other purpose. Depending on which type of network you use, Wi-Fi or cable connection, there are two ways to find your MAC address, and I will cover both of them.

Wi-Fi

If you are using a Wi-Fi connection to access the Internet, then finding the MAC address of your wireless network card is very easy. All you have to do is hold down the "Option" key and click on the Wi-Fi icon from the menu bar. Once you have done that, you will see your network card's address, the name of the interface and other options (see image). If, by some chance, this doesn't work because you are using an older version of OS X (or if your Wi-Fi is turned off), you can click on the "Network Preferences" option and select the "Hardware" tab to view the address. Additionally, you can access the "System Preferences" menu, navigate to your "Network" tab, select your Wi-Fi network, click on "Advanced" and select the "Hardware" tab.

Wi-Fi Mac Address

Keep in mind that the displayed address is the physical address of your Mac, so, if it was previously changed, you might want to find the actual address by writing the following command under Terminal:

ifconfig en0 | grep ether

Show MAC Command

Typically, the network interface on your Mac is given the name en0. If, by some chance the ifconfig command doesn't return a value, you might want to try replacing en0 with en1.

Cable connection

If you are using a cable connection to access the Internet on your system, then, in order to find the MAC address of your Ethernet network card, you will have to do it several simple steps. First, you will have to access the "System Preferences" from the Apple menu. Once you have done that, open the "Network Preferences" window, select your Ethernet connection on the left side, click on the "Advanced" button and then on the "Hardware" tab. Now you will see the MAC address of your Ethernet network card.

Ethernet MAC Address

Same as with the Wi-Fi MAC address, if your Ethernet address has been changed or if you want to make sure you will get the actual address, then it is recommended to use the "ifconfig en0 (or en1) | grep ether" command.

Changing the MAC address

Now that you know how to find the MAC address of your network card, it is time to change it. First of all, as you might have noticed, the MAC address has a specific format that follows this pattern: aa:bb:cc:dd:ee:ff. So, if you want to change your network address, then you will have to provide one or, if you don't have one in mind, you can always generate a random one using the Terminal and typing the following command:

openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'

Once you have your MAC address ready, all you have to do is open the Terminal and use this command to spoof the address:

sudo ifconfig en0 ether aa:bb:cc:dd:ee:ff

Obviously, you will have to replace the generic MAC address that I've provided (aa:bb:cc:dd:ee:ff) with the one you have generated or the one you desire to replace it with. Moreover, just as before, some systems use en1 instead of en0 when referring to the network interface, so, make sure you use the correct one.

For example, if you want to change the MAC address to, let's say, 00:b1:b2:b3:b4:b5, then the command will look like this:

sudo ifconfig en0 ether 00:b1:b2:b3:b4:b5

Additionally, can use a randomly generated MAC address to change your original one, without having to writing it down and using it later with the above mentioned command, by combining the sudo and the generation command, like this:

openssl rand -hex 6 | sed 's/$..$/\1:/g; s/.$//' | xargs sudo ifconfig en0 ether

The effects of using these commands to change your MAC address will be reverted once you have restarted your system. So, if you want to make these changes permanent, you might want to create a script that will run every time you start your computer.

Using third-party apps

Ultimately, if you don't want to work with the Terminal and manually change your MAC address, then you can always download and install various third-party applications that can help you do that. Two examples of such tools are MacDaddy and MacSpoofer, both of the free and very easy to use.

Conclusion

As you can see, changing your MAC address is not that complicated. However, you should know that, after spoofing these addresses, you might encounter some network problems, so it is highly recommended to restart your network connections.

Also, if you are having trouble changing the MAC address of your Wi-Fi network card, you might want to make sure that the Airport is turned on at all times.