Internet, Networking, & Security Home Networking How to Filter MAC Addresses to Block Devices on Your Network Stop unknown devices from connecting to your Wi-Fi network by Tony Bradley, CISSP-ISSAP Writer Tony Bradley is a former Lifewire writer and tech journalist who specializes in network and internet security. He is a respected information security expert and prolific author. our editorial process LinkedIn Tony Bradley, CISSP-ISSAP Updated on November 09, 2019 Alexandru Magurean / E+ / Getty Images Home Networking The Wireless Connection Routers & Firewalls Network Hubs ISP Broadband Ethernet Installing & Upgrading Wi-Fi & Wireless Tweet Share Email If you've changed the default password and SSID on your router, you've already connected one piece of the security puzzle that an attacker would have to crack before they could get into your network. However, there's no need to stop there when you can take additional measures. Most wireless network routers and access points let you filter devices based on their MAC address, which is a device's physical address on the network. If you enable MAC address filtering, only the devices with MAC addresses configured in the wireless router or access point will be allowed to connect. The MAC address is a unique identifier for networking hardware such as wireless network adapters. While it's definitely possible to spoof the MAC address so the attacker can pretend to be an authorized user, no casual hacker or curious snooper will go to such lengths, so MAC filtering will still protect you from the majority of users. There are other types of filtering that can be done on a router that are different than MAC filtering. For example, content filtering is when you prevent certain keywords or website URLs from passing through the network. Instructions in this article apply to all versions of Windows and macOS. How to Find Your MAC Address in Windows This technique will work in all versions of Windows: Open the Run dialog box by using the Win+R keys. That is, the Windows key and the R key. Type cmd in that small window that opens. This will open Command Prompt. Type ipconfig /all in the Command Prompt window. Press Enter to submit the command. You should see a bunch of text show up within that window. Find the line labeled Physical Address or physical access address. That is the MAC address for that adapter. If you have more than one network adapter, you will need to look through the results to make sure you get the MAC address from the correct adapter. There will be a different one for your wired network adapter and your wireless one. How to Locate the MAC Address on a Mac The process for finding the MAC address for filtering on a Mac desktop or laptop computer is slightly different. Here's how it works. Select System Preferences under the Apple menu. Click Network. Select Wi-Fi in the left pane. Click the Advanced button. Your MAC address appears next to Wi-Fi Address. How to Filter MAC Addresses in Your Router Refer to your owner's manual for the wireless network router or access point you are using to learn how to access the configuration and administration screens and enable and configure MAC address filtering to protect your wireless network. For example, if you have a TP-Link router, you can follow the instructions on their website to configure wireless MAC address filtering. Some NETGEAR routers hold the setting in the ADVANCED > Security > Access Control screen. MAC filtering on a Comtrend AR-5381u router is done through the Wireless > MAC Filter menu like you see here. To find the support pages for your specific router, just do an online search for the make and model, something like "NETGEAR R9000 MAC filtering."