Your Mac address stays the same unless you change your network hardware or spoof it intentionally

A Mac address (media access control address) is a unique identifier assigned to your network card — the physical hardware that connects your device to a network. It looks like six pairs of numbers and letters: 00:1A:2B:3C:4D:5E. Your Mac address does not change when you move to a different WiFi network, switch internet providers, or restart your device. It only changes if you replace the network card itself, if your operating system assigns a new one during a factory reset, or if you deliberately change it using software tools.

The confusion usually comes from mixing up Mac addresses with IP addresses. Your IP address changes regularly — every time you connect to a new network or your internet provider assigns you a new one. Your Mac address is tied to the physical hardware and stays constant on the same device, which is why it is useful for identifying devices on a local network.

Key Takeaways

  • Your Mac address is burned into your network card and remains the same across different WiFi networks and internet providers.
  • Restarting your device, changing networks, or getting a new IP address does not change your Mac address.
  • Replacing your network card, performing a factory reset, or using Mac address spoofing software can change your Mac address.
  • Network administrators use Mac addresses to identify devices on a local network, so a changed Mac address may trigger security alerts.

Why your Mac address stays the same on different networks

Your Mac address is assigned by the manufacturer of your network card and is hardcoded into the card's firmware. When you connect to a coffee shop WiFi, your home network, or a corporate office network, your device sends the same Mac address to each one. The network uses that address to identify your device on the local network and assign it a local IP address — but the Mac address itself never changes just because you moved to a different WiFi.

This is different from your public IP address, which your internet service provider assigns and can change. Your Mac address is local-only — it does not travel across the internet the way your IP address does. Routers and switches on the same network segment can see your Mac address, but devices on other networks cannot.

When your Mac address actually changes

Your Mac address changes in a few specific situations. If you replace your network card — whether it is a WiFi card in a laptop, an Ethernet card in a desktop, or the network hardware in a phone — the new card has a different Mac address. If you perform a factory reset on some devices, the operating system may assign a new Mac address, though this is less common on modern systems.

You can also change your Mac address deliberately using software. On Windows, you can change it through Device Manager or using third-party tools. On Mac, you can use terminal commands to spoof your Mac address. On Linux, tools like macchanger let you set a temporary Mac address. These changes are usually temporary — they revert when you restart your device — unless you make them permanent through your network driver settings.

Why someone might change their Mac address

Network administrators sometimes change Mac addresses to test network security or to bypass access controls that are based on Mac address filtering. Developers working on network software may spoof Mac addresses to simulate multiple devices on a test network. Some people change their Mac address for privacy reasons, though this only affects what devices on your local network can see about you — it does not hide your activity from your internet service provider or websites you visit.

Changing your Mac address can trigger security alerts on corporate or institutional networks, since network monitoring tools flag unexpected Mac address changes as a sign of device tampering or unauthorized hardware. If you are on a managed network, changing your Mac address may disconnect you or lock your device out until an administrator investigates.

How to find your Mac address

On Windows, open Command Prompt and type ipconfig /all. Look for "Physical Address" — that is your Mac address. On Mac, go to System Preferences, click Network, select your connection, and click Advanced. Your Mac address is listed as "Wi-Fi Address" or "Ethernet Address" depending on your connection type. On Linux, open a terminal and type ip link show or ifconfig to see your Mac address next to "HWaddr" or "ether".

If you have multiple network cards — for example, both WiFi and Ethernet — each one has its own Mac address. The one you see depends on which network interface you are looking at. Most of the time you only need to know the Mac address of the connection you are currently using.

Mac address filtering and network security

Some routers and networks use Mac address filtering to control which devices can connect. A router can be set to allow only specific Mac addresses, or to block certain ones. If your Mac address is on the allowed list, you can connect. If it is not, the network will reject your device even if you have the correct WiFi password.

This is a weak form of security because Mac addresses can be spoofed — someone can change their Mac address to match an allowed one and gain access. More find networks use WPA3 encryption or certificate-based authentication instead. But Mac address filtering is still common in offices, schools, and homes where the goal is to prevent casual access rather than to stop a determined attacker.

The difference between Mac address and device name

Your device name (also called hostname) is what appears in your network settings and is visible to other devices on the network. You can change your device name anytime without affecting your Mac address. Your device name is James-MacBook or Living-Room-PC — something you choose. Your Mac address is A4:5E:60:D1:2C:3F — something the manufacturer assigned.

Networks can identify your device by either name or Mac address. Changing your device name does not change how the network sees you at the hardware level. Changing your Mac address does not change your device name. They are separate identifiers that serve different purposes.

Frequently Asked Questions

Does restarting my device change my Mac address?

No. Restarting your device does not change your Mac address. If you spoofed your Mac address before the restart, it will revert to the original address after restart, but that is because the spoofing was temporary — not because the restart itself changed anything.

Will my Mac address change if I get a new IP address?

No. Your IP address and Mac address are independent. You can get a new IP address from your router or internet provider without your Mac address changing at all. They identify your device at different layers of the network.

Can someone track me using my Mac address?

Only on the local network you are connected to. Your Mac address does not travel across the internet, so websites and internet services cannot see it. Your internet service provider and network administrator can see it, but only for devices on their network.

What happens if two devices have the same Mac address?

Network problems occur. The router or switch cannot tell the devices apart and may send data to the wrong one. This is why Mac addresses are supposed to be unique — manufacturers assign them to avoid this. If you spoof your Mac address to match another device on the same network, you will cause conflicts.

Is changing my Mac address illegal?

Changing your own Mac address on your own device is legal. Using a spoofed Mac address to bypass network security or gain unauthorized access to a network is illegal. The legality depends on intent and whether you have permission to be on the network.