A MAC address is a unique identifier assigned to every device that connects to a network

Every network device — your laptop, phone, printer, smart TV — has a MAC address (Media Access Control address), a string of characters that identifies it on a local network. It looks something like 00:1A:2B:3C:4D:5E and serves as a physical address for your device, separate from your IP address. While an IP address routes data across the internet, a MAC address routes data within your home network or office network.

Your device's MAC address is burned into its network hardware when it's manufactured. You cannot change it permanently, though some devices let you spoof it temporarily for troubleshooting. Your router uses MAC addresses to recognize which devices are connected to it and to assign them IP addresses through DHCP (Dynamic Host Configuration Protocol).

Key Takeaways

  • A MAC address identifies your device on a local network, while an IP address identifies it on the internet.
  • MAC addresses are assigned by the manufacturer and built into your device's network hardware.
  • Your router uses MAC addresses to recognize connected devices and assign them IP addresses.
  • You can find your MAC address in your device's network settings or by running a command on your computer.
  • MAC filtering allows routers to block or allow specific devices based on their MAC address.

How MAC addresses work on your home network

When you connect a device to your Wi-Fi, your router broadcasts a signal. Your device responds with its MAC address, and the router records it. The router then assigns your device a temporary IP address from a pool of available addresses. This happens automatically and invisibly — you do not have to do anything.

The router keeps a table of MAC addresses and their assigned IP addresses. When data arrives at your router from the internet destined for a specific IP address, the router looks up which MAC address is associated with that IP and sends the data to the correct device. This is how your router knows to send an email to your laptop instead of your phone, even though both are on the same network.

MAC addresses only matter on your local network. Once data leaves your home network and travels across the internet, routers use IP addresses instead. Your ISP and websites you visit do not see your MAC address — they see only your public IP address.

Where to find your MAC address

On Windows, open Command Prompt and type ipconfig /all, then press Enter. Look for "Physical Address" in the results — that is your MAC address. You can also find it in Settings by going to Network & Internet, then Status, then Advanced Network Settings, then scroll down to find your network adapter and its MAC address listed there.

On Mac, open System Preferences, go to Network, select your active connection, then click Advanced. The MAC address appears under the Wi-Fi tab as "Wi-Fi Address." On iPhone or iPad, go to Settings, then General, then About, and look for "Wi-Fi Address." On Android, go to Settings, then About Phone, then Status, and look for "Wi-Fi MAC Address."

If you need your printer's or router's MAC address, check the device's settings menu or the label on the back of the device. Most routers print their MAC address on a sticker underneath.

MAC filtering and network security

Some routers offer MAC filtering, a security feature that lets you create a list of allowed or blocked MAC addresses. If you enable MAC filtering to allow only certain devices, your router will refuse to connect any device whose MAC address is not on the list. This prevents unauthorized devices from joining your network, even if someone knows your Wi-Fi password.

MAC filtering is not a complete security solution — someone with technical knowledge can spoof a MAC address to impersonate an allowed device. But it adds a layer of protection, especially in homes with many devices where you want to prevent guests' phones from connecting without permission. Most home users do not need MAC filtering if they use a strong Wi-Fi password and keep their router firmware updated.

Why your device might have multiple MAC addresses

Some devices have more than one MAC address because they have multiple network adapters. A laptop with both Wi-Fi and Ethernet ports has two MAC addresses — one for the Wi-Fi adapter and one for the wired connection. A phone with Wi-Fi and Bluetooth has separate MAC addresses for each. Your router only sees the MAC address of whichever connection is currently active.

Some devices also randomize their MAC address for privacy reasons. Newer iPhones and Android phones can use a different MAC address each time they scan for networks, which prevents tracking apps from identifying your device by its hardware address. This is called MAC address randomization and is a privacy feature, not a sign of a problem.

MAC addresses versus IP addresses

The difference matters for understanding how networks work. A MAC address is a hardware identifier that works only on your local network — it gets you from your device to your router. An IP address is a logical identifier that works across the internet — it gets data from your router to a server across the world. Think of a MAC address as your home address and an IP address as your mailing address.

When you visit a website, your device sends a request with both its MAC address and its IP address. Your router uses the MAC address to find your device on the local network. The internet uses the IP address to route the request to the correct server and back. The server sees only your IP address, not your MAC address.

Frequently Asked Questions

Can someone track me using my MAC address?

Not across the internet — your MAC address does not leave your local network. However, someone on your Wi-Fi network could theoretically identify your device by its MAC address. Websites and apps cannot see your MAC address. If you are concerned about local tracking, enable MAC address randomization in your device settings, which most modern phones do by default.

What happens if two devices have the same MAC address?

This should not happen because manufacturers assign unique MAC addresses to each device. If it does occur, your router will become confused about which device is which, and one or both devices may lose network connection. This is rare but can happen if someone manually spoofs a MAC address. Restart both devices to fix it.

Do I need to know my MAC address for anything?

Most of the time, no. You only need it if you are setting up MAC filtering on your router, registering a device with your internet provider, or troubleshooting network problems. Your router handles MAC addresses automatically in normal use.

Can I change my MAC address permanently?

No, not permanently. Your MAC address is hardcoded into your device's network hardware by the manufacturer. Some operating systems let you spoof it temporarily for testing, but it resets when you restart. Permanent changes require replacing the network hardware itself.

Why does my device show a different MAC address than before?

Your device is likely using MAC address randomization for privacy. Newer phones and laptops randomize their MAC address when scanning for networks or connecting to new networks. This is intentional and normal — it prevents apps and networks from tracking your device by its hardware address.