What Is a MAC Address? (And Can Websites See It?)

Q: What is a MAC address?

A MAC address is a permanent 48-bit hardware identifier built into every network interface, written as six hex pairs like 00:1A:2B:3C:4D:5E. The first three pairs identify the manufacturer and the rest are unique to your device. It identifies your device on the local network, unlike an IP address which identifies your position on the internet.

Q: How do I find my MAC address?

On Windows run "ipconfig /all" and read the Physical Address. On macOS open System Settings, Network, your connection, Details, Hardware. On iPhone or Android go to Wi-Fi settings and tap the connected network to see the Wi-Fi or MAC address. On Linux run "ip link" in a terminal.

Q: Can a website see my MAC address?

No. A MAC address does not travel past your router, so a remote website only ever sees your public IP address, never your MAC. Websites recognize you through browser fingerprinting and cookies, not your hardware address.

Q: Does my MAC address change?

The hardware MAC is fixed, but modern phones often present a randomized MAC per network for privacy, on by default on recent iOS and Android Wi-Fi. Desktop behavior varies by operating system and settings, and you can usually toggle randomization per network in Wi-Fi settings.

Q: What is a MAC address used for?

It is used to deliver data between devices on the same local network, for the router to track DHCP leases, and for MAC filtering where a network allows or blocks specific devices. It is a local-network identifier, not something used to route traffic across the internet.

~/sheets/what-is-a-mac-address.md

What a MAC Address Actually Is
A MAC (Media Access Control) address is a permanent hardware identifier burned into every network interface — your Wi-Fi card, your Ethernet port, your phone radio. It is a 48-bit number, written as six pairs of hexadecimal digits like 00:1A:2B:3C:4D:5E. The first three pairs identify the manufacturer (the OUI, or Organizationally Unique Identifier); the last three are unique to your specific device.
The key thing to understand: a MAC address works at the local network layer (Layer 2). It identifies your device on your own network — between your laptop and your router, for example. It is not the same thing as your IP address, which identifies your network position on the wider internet.
How to Find Your MAC Address
Windows: open Command Prompt and run ipconfig /all; look for "Physical Address." macOS: System Settings > Network > (your connection) > Details > Hardware. iPhone/Android: Settings > Wi-Fi > tap the connected network; it is listed as "Wi-Fi Address" or "MAC address." Linux: run ip link in a terminal.
Can a Website See Your MAC Address?
No. This is the most common myth about MAC addresses. A MAC address does not travel past your router — it is stripped and replaced at each network hop, so a remote website only ever sees your public IP address, never your MAC. What websites actually use to recognize you is browser fingerprinting and cookies, not your hardware address. If you are worried about being tracked online, your MAC address is not the exposure to fix — your IP and your browser fingerprint are.
Where Your MAC Address Does Matter
Your MAC is visible to anyone on the same local network: the router admin, the coffee-shop Wi-Fi operator, or someone running a sniffer on public Wi-Fi. Networks use it for MAC filtering (allow/deny lists) and DHCP lease tracking. On public Wi-Fi the operator can see which device (by MAC) connected and when.
MAC Randomization and Privacy
Because a fixed MAC could let networks track a device across locations, modern phones often randomize the MAC address they present per network. This is on by default on recent iOS and Android versions for Wi-Fi, though desktop operating systems vary and the behavior depends on your OS version and settings. You can usually toggle it per-network under the Wi-Fi settings ("Private Wi-Fi Address" on iOS, "Randomized MAC" on Android).
The Bottom Line
A MAC address identifies hardware on the local network; your IP identifies your network location online. For online privacy, focus on what is actually exposed: run a Privacy Checkup, check what your IP reveals, and test how unique your browser fingerprint is. Your MAC address stays local and is not what websites track you by.
Frequently Asked Questions
What is a MAC address?
A MAC address is a permanent 48-bit hardware identifier built into every network interface, written as six hex pairs like 00:1A:2B:3C:4D:5E. The first three pairs identify the manufacturer and the rest are unique to your device. It identifies your device on the local network, unlike an IP address which identifies your position on the internet.
How do I find my MAC address?
On Windows run "ipconfig /all" and read the Physical Address. On macOS open System Settings, Network, your connection, Details, Hardware. On iPhone or Android go to Wi-Fi settings and tap the connected network to see the Wi-Fi or MAC address. On Linux run "ip link" in a terminal.
Can a website see my MAC address?
No. A MAC address does not travel past your router, so a remote website only ever sees your public IP address, never your MAC. Websites recognize you through browser fingerprinting and cookies, not your hardware address.
Does my MAC address change?
The hardware MAC is fixed, but modern phones often present a randomized MAC per network for privacy, on by default on recent iOS and Android Wi-Fi. Desktop behavior varies by operating system and settings, and you can usually toggle randomization per network in Wi-Fi settings.
What is a MAC address used for?
It is used to deliver data between devices on the same local network, for the router to track DHCP leases, and for MAC filtering where a network allows or blocks specific devices. It is a local-network identifier, not something used to route traffic across the internet.
Last updated: April 2026