What a MAC address is and why you need it

A MAC address is a unique identifier assigned to your laptop's network card — the hardware that connects you to WiFi or ethernet. It looks like six pairs of letters and numbers separated by colons: a4:5e:60:c2:f8:19. Every device on your network has one, and it never changes.

When you set up a home network with security controls, you often need to tell your router which devices are allowed to connect. The router uses MAC addresses to recognize your laptop, phone, tablet, and other devices. Some routers also use MAC filtering — a feature that blocks any device whose MAC address is not on an approved list. To add your laptop to that list, you need its MAC address first.

You may also need it if you are troubleshooting connection problems with your internet provider, setting up a guest network, or configuring advanced security features like MAC address cloning.

Key Takeaways

  • Your MAC address is a unique identifier for your laptop's network card, shown as six pairs of characters like a4:5e:60:c2:f8:19.
  • On Windows, open Settings, go to Network & Internet, then Advanced Network Settings, and look for "Physical Address" next to your active connection.
  • On Mac, open System Settings, click Network, select your WiFi or ethernet connection, and find "MAC Address" in the details.
  • On Linux, open a terminal and type ip link show or ifconfig to see the address labeled "HWaddr" or "ether".
  • Write down or screenshot your MAC address before you configure router security settings, because you will need it to add your laptop to the approved device list.

Finding your MAC address on Windows 10 or 11

Open the Settings app by pressing the Windows key and typing "Settings", then press Enter. Click Network & Internet in the left sidebar.

Look for Advanced Network Settings near the bottom of the page and click it. Scroll down until you see a section labeled Related Settings or More Network Options. Click View Your Network Properties or Advanced Network Settings again if you see it listed.

You will see a list of your network connections. Find the one you are currently using — it will be labeled either WiFi or Ethernet depending on how your laptop connects. Click on it. In the details panel that opens, scroll down and look for Physical Address. The string of characters next to it is your MAC address. Copy it exactly as shown, including the hyphens.

Finding your MAC address on macOS

Click the Apple menu in the top-left corner and select System Settings (or System Preferences on older versions). Click Network in the sidebar.

Select the connection you are using — WiFi if you are on wireless, or Ethernet if you are plugged in. Click the Details or Advanced button. Look for MAC Address in the window that opens. It will be displayed as six pairs of characters separated by colons.

If you do not see a Details button, try clicking the gear icon at the bottom of the connection list and selecting Advanced from the menu that appears.

Finding your MAC address on Linux

Open a terminal window. Type the command ip link show and press Enter. Your MAC address will appear next to the word link/ether on the line for your active connection.

If that command does not work, try ifconfig instead. Look for the line labeled HWaddr — that is your MAC address. It will be the same format: six pairs of characters separated by colons.

What to do once you have your MAC address

Write down or take a screenshot of your MAC address and keep it somewhere you can find it later — a notes app, a document, or a piece of paper. You will need it when you log into your router to configure security settings.

Most routers have a web interface you access by typing your router's IP address into a browser — usually something like 192.168.1.1 or 192.168.0.1. Once you are logged in, look for a section called Device Management, Connected Devices, MAC Filtering, or DHCP Reservation. The exact name depends on your router model. You will paste your laptop's MAC address into the appropriate field to add it to your approved devices list or to reserve a specific local IP address for it.

If you are setting up MAC filtering — a feature that blocks any device not on your approved list — make sure you have the MAC addresses for all the devices you want to allow before you enable it. If you forget a device's address and enable filtering, that device will not be able to connect until you add it.

Common mistakes when using MAC addresses

The most common error is copying the address incorrectly. MAC addresses are case-insensitive, so A4:5E:60 and a4:5e:60 are the same. However, the colons or hyphens must be in the right places. If your router asks for the address without separators, remove them — type a45e60c2f819 instead of a4:5e:60:c2:f8:19. Check your router's documentation to see which format it expects.

Another mistake is confusing your laptop's MAC address with your router's MAC address. Your router also has a MAC address, but that is not what you need for device filtering. You need the address of the network card inside your laptop.

If you have both WiFi and ethernet on your laptop, you have two different MAC addresses — one for each connection. If you plan to use both, write down both addresses. Most routers let you add multiple devices, so you can approve both.

Frequently Asked Questions

Can someone use my MAC address to hack my network?

A MAC address alone is not enough to hack your network — it is visible to anyone on the same WiFi network. What matters is whether your router uses MAC filtering as part of a broader security setup. If you have a strong WiFi password and WPA3 encryption enabled, MAC filtering adds a second layer but is not a substitute for those basics.

Will my MAC address change if I restart my laptop?

No. Your MAC address is burned into your network card hardware and does not change when you restart, update your operating system, or move to a different location. It stays the same for the life of that network card. If you replace the network card, you get a new MAC address.

What if I cannot find the MAC address in Settings?

Make sure you are looking at the right connection — the one you are actually using to connect to the internet. If you are on WiFi, do not look at the ethernet settings. If Settings does not show it clearly, try the command-line method for your operating system instead. It is usually faster and more reliable.

Do I need to do anything special to use my MAC address with the router?

No. straightforward log into your router's web interface, find the device management or MAC filtering section, and paste your laptop's MAC address into the appropriate field. Your router's manual or support page will tell you exactly where that section is and what format it expects.