What a MAC Address Is and Why You Might Change It

A MAC address (Media Access Control address) is a unique identifier assigned to your network card — the hardware that connects your computer to the internet. It looks like six pairs of numbers and letters, such as 00:1A:2B:3C:4D:5E. Your router uses this address to recognize your device on the local network.

You might change your MAC address to test network security, troubleshoot connection problems, bypass a network filter that blocks your device, or replace a network card that has failed. Changing it is a temporary software change on most systems — when you restart, the original address returns unless you make the change permanent.

The process differs between Windows, macOS, and Linux because each operating system manages network hardware differently. All three methods are straightforward and do not require special software or administrator privileges beyond what you already have.

Key Takeaways

  • On Windows, you change your MAC address through Device Manager by editing the network adapter's registry settings or using the network adapter's own settings panel.
  • On macOS, you use Terminal commands to change the address, and the change lasts until you restart or manually revert it.
  • On Linux, you use Terminal commands with ifconfig or ip to bring the interface down, change the address, and bring it back up.
  • After changing your MAC address, restart your router or reconnect to the network so it recognizes the new address.
  • The change is usually temporary — restarting your computer restores the original address unless you configure it to persist.

Changing Your MAC Address on Windows

On Windows, the easiest method is through your network adapter's settings panel if the manufacturer provided one. Open Device Manager by right-clicking the Start button and selecting Device Manager. Expand Network adapters, right-click your active network adapter (usually labeled Ethernet or Wi-Fi), and select Properties.

Look for an Advanced tab. If your network adapter manufacturer included a settings panel, you will see a list of properties on the left. Look for an entry labeled MAC Address, Locally Administered Address, or Network Address. Select it, and on the right side you will see a Value field. Enter your new MAC address as six pairs of hexadecimal characters (0–9 and A–F) separated by hyphens, such as 02-1A-2B-3C-4D-5E. Click OK and close Device Manager.

If your network adapter does not have an Advanced tab or MAC Address option, you can change it through the Windows Registry. Press Windows Key + R, type regedit, and press Enter. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}. Look through the numbered folders (0000, 0001, etc.) until you find one where the DriverDesc value matches your network adapter name. In that folder, create a new String Value called NetworkAddress, and set its value to your new MAC address without hyphens, such as 021A2B3C4D5E. Restart your computer for the change to take effect.

Changing Your MAC Address on macOS

On macOS, you use Terminal to change your MAC address. Open Terminal (found in Applications > Utilities) and first identify your network interface name by typing ifconfig and pressing Enter. Look for the interface you want to change — usually en0 for Ethernet or en1 for Wi-Fi. Note the current MAC address listed as ether.

To change the address, type the following command, replacing en0 with your interface name and the address with your new MAC address:

sudo ifconfig en0 lladdr 00:1A:2B:3C:4D:5E

Press Enter and type your password when prompted. The change takes effect when ready. To verify it worked, type ifconfig again and check that the ether value for your interface has changed. When you restart your computer, the original MAC address returns. If you want the change to persist across restarts, you can create a script that runs this command at startup, but that requires editing your system launch files.

Changing Your MAC Address on Linux

On Linux, you change your MAC address using Terminal commands. First, identify your network interface by typing ip link show or ifconfig and pressing Enter. Note the interface name — usually eth0 for Ethernet or wlan0 for Wi-Fi.

Bring the interface down by typing sudo ip link set dev eth0 down, replacing eth0 with your interface name. Then change the MAC address with sudo ip link set dev eth0 address 00:1A:2B:3C:4D:5E, again replacing the interface name and entering your new address. Finally, bring the interface back up with sudo ip link set dev eth0 up.

Verify the change by typing ip link show again. The new address should appear next to link/ether. This change lasts until you restart. To make it permanent, edit your network configuration file (usually in /etc/network/interfaces or /etc/netplan/ depending on your distribution) and add the address setting there, then restart networking or reboot.

What to Do After Changing Your MAC Address

After you change your MAC address, your router and other network devices still recognize your old address. Disconnect from your network and reconnect, or restart your router so it clears its device list and recognizes your computer under the new address. This usually takes 30 seconds to a minute.

If you are on Wi-Fi, forget the network in your system settings, then reconnect and re-enter the password. If you are on Ethernet, unplug the cable for 10 seconds and plug it back in. Your computer will request a new IP address from the router, and the network will recognize it by the new MAC address.

Common Mistakes to Avoid

The most common mistake is using an invalid MAC address format. MAC addresses must be hexadecimal (digits 0–9 and letters A–F only) and follow the pattern of six pairs separated by colons or hyphens. If you enter a letter like G or Z, the change will fail silently or produce an error.

Another mistake is forgetting that the change is temporary. If you restart your computer and the address reverts to the original, that is normal behavior — the system is designed to restore the hardware address on startup. If you need the change to survive a restart, you must configure it in your system files or network settings.

Do not change your MAC address to impersonate another device on the same network. If two devices have the same MAC address, both will lose network connectivity. If you are testing network security, use a MAC address that does not belong to any device on your network.

When You Might Need to Revert Your MAC Address

If you changed your MAC address and now cannot connect to the network, the quickest fix is to restart your computer. The original address will return, and your connection should work again. If restarting does not help, manually revert the address using the same steps you used to change it — just enter your original MAC address instead.

If you do not remember your original MAC address, you can usually find it in your network adapter's properties or printed on a sticker on the device itself. On Windows, open Device Manager, right-click your network adapter, select Properties, and look for a Permanently Burned-In Address or similar field. On macOS or Linux, if you have not restarted yet, your original address is still visible in the output of ifconfig or ip link show — look for a second address listed as the permanent one.

Frequently Asked Questions

Will changing my MAC address hide my identity online?

No. Your MAC address is only visible to devices on your local network (your router and other computers on the same Wi-Fi or Ethernet). Websites and internet services see your IP address and other identifiers, not your MAC address. Changing your MAC address does not make you anonymous online.

Can I use any MAC address I want?

Technically yes, but you should follow the format rules: six pairs of hexadecimal characters. The first pair should start with an even number (0, 2, 4, 6, 8, A, C, E) if you want to avoid conflicts with manufacturer-assigned addresses. Never use the same MAC address as another device currently on your network.

Does changing my MAC address affect my internet speed?

No. Your MAC address is only used for local network communication. It does not affect your connection speed, bandwidth, or how your internet service provider sees you.

What if my network adapter does not have an Advanced tab in Device Manager?

Some older or generic network adapters do not include a MAC address setting in their properties panel. In that case, use the Registry method described in the Windows section, or contact your network adapter manufacturer to see if they provide a utility for changing the address.

How do I make the MAC address change permanent on Linux?

Edit your network configuration file. On systems using netplan (Ubuntu 18.04 and later), edit /etc/netplan/01-netcfg.yaml and add macaddress: 00:1A:2B:3C:4D:5E under your interface settings. On systems using /etc/network/interfaces, add a line like hwaddress 00:1A:2B:3C:4D:5E under your interface block. Save the file and restart networking with sudo systemctl restart networking.