Wi-Fi MAC Randomisation on Android: What It Does and Why You Want It

Most of us don't think twice about our phones connecting to Wi-Fi. You walk into a coffee shop, your phone sees the SSID, and it connects. But behind the scenes, your phone has a unique hardware ID called a MAC address. Think of it like a permanent digital social security number for your phone's Wi-Fi chip. For years, every time you walked past a store or mall with Wi-Fi, your phone would broadcast this static ID. This made it incredibly easy for shops or data brokers to track your movement. If you visited a grocery store on Monday and came back Friday, they knew it was the exact same person because your MAC address never changed. Thankfully, Android now randomises this by default, but there are some nuances you should know to make sure you're actually protected.

What MAC randomisation is

MAC stands for Media Access Control. It’s a 12-character string (like 00:1A:2B:3C:4D:5E) that is hard-coded into your phone's hardware at the factory. In the old days of Android, your phone used this "real" address for every connection. If you were walking down a busy street with Wi-Fi turned on, your phone was constantly sending out probes to see which networks were nearby. Each probe contained your unique MAC address.

MAC randomisation changes the rules. Instead of broadcasting that permanent hardware ID, your phone generates a "fake" MAC address for each network it encounters. To a tracking sensor in a department store, you look like a brand new device every time you visit, or at least a device that doesn't link back to your personal identity. It's essentially digital camouflage for your hardware.

I remember when I first dug into my Pixel's settings to check this. I assumed it worked everywhere, all the time. But there's a catch: randomisation usually happens per network. This means if you connect to the Wi-Fi at your local gym, Android generates a random MAC for that specific gym. As long as you stay on that network, the gym sees that same "fake" address. If you come back tomorrow, your phone usually identifies itself with that same fake ID so the network doesn't get confused. This is a compromise between privacy and the practical need for a network to remember who you are so you don't have to sign into a splash page every five minutes.

The default behaviour

If you're on a relatively modern phone — anything running Android 10, 11, or the newer versions like Android 14 and 15 — randomisation is turned on by default for almost every new connection. You don't have to toggle a master switch. However, the way it randomises has changed over the years. In older versions, it was a bit hit-or-miss, but on Google's current implementation, it's quite aggressive.

How to verify it on your phone

You can see this in action right now. Open your Settings app and go to Network & internet (it might just say Connections on a Samsung). Tap on Internet or Wi-Fi, and then tap the gear icon next to the network you're currently using. Look for a section labeled Privacy. On my Pixel, it says "Use randomised MAC (default)." Directly below that, you'll see the MAC address currently being shared. If that address starts with a certain sequence (often starting with a '2', '6', 'A', or 'E' in the second character), it’s a randomised one.

It’s worth mentioning that while this is the default, it isn't foolproof. Some older routers or public "captive portals" (the pages that make you "Accept Terms" to get free Wi-Fi) don't play nice with randomised addresses. They expect a hardware address that never changes. If you've ever had a public Wi-Fi network keep kicking you off every 10 minutes, there is a high chance the router is getting confused by your phone trying to be private. This is the one annoying part of modern privacy: sometimes old tech just breaks when we try to stay secure.

Per-network override

There are times when you actually want to turn this off. I know that sounds counterintuitive in a privacy guide, but it's a practical reality. For example, I have a mesh Wi-Fi system at home where I've set up "Static IPs" for my devices so I can manage them easily. If my phone keeps changing its identity, my router can't apply the rules I've set for it.

To change this for a specific network, follow these steps:

1. Go to Settings > Network & internet > Wi-Fi.
2. Tap the gear icon next to the specific network (like your home Wi-Fi).
3. Tap Privacy.
4. Select Use device MAC.

Once you do this, your phone will reveal its "true" hardware ID to that specific router. I only recommend doing this for networks you completely trust, like your home or your office. For any public Wi-Fi at a Starbucks, airport, or hotel, you should absolutely leave it on "Randomised."

Here is a concrete example of why this matters: Imagine a shopping mall with 50 different Wi-Fi access points. If you have randomisation off, the mall's analytics software can see exactly which stores you visited, how long you stood in front of the window at the electronics store, and even what floor you spent the most time on. They can then sell that profile to advertisers. By using a randomised MAC, you're essentially just a "guest" who appeared once and disappeared, making that data much less valuable to them. It won't stop a dedicated hacker from trying to sniff your traffic, but it stops the passive, massive-scale tracking that has become the norm in retail environments.

Just a small caveat: MAC randomisation doesn't hide your IP address or what websites you’re visiting. Think of it as hiding your license plate, not your face. To hide your actual activity, you still need to rely on HTTPS and potentially a VPN, but keeping your "digital license plate" hidden is a great first step.