Apple built in privacy protection for an issue adjacent to your IP address. Every Ethernet or Wi-Fi adapter, built in or plugged in, has a unique MAC address—that’s Media Access Control, not Macintosh. A MAC address appears in the form xx:xx:xx:xx:xx:xx, where each x is a value between 0 and 15 expressed in hexadecimal (0 to 9 then A to F). Apple perplexingly calls it a “Wi-Fi address”, which is the incorrect name.
A MAC address is how a device communicates over a local network, used to make sure every interface has a unique address to avoid data being delivered to the wrong location. However, because this MAC address is set in hardware, clever hackers and marketers started to use it to associate people with devices—your MAC address persisted indefinitely, so a Wi-Fi router in a public place could conceivably track you over time whenever you connected to any router that shared information with a central database, like a cell carrier or ad-targeting service. Bad!
Apple got around this by adding a “Private Wi-Fi address” option (still the wrong term) that generates a unique MAC address for each Wi-Fi network you join, changing it from time to time. This deters and potentially fully prevents MAC-based tracking.
Apple made significant changes to this several-year-old feature in iOS 18/iPadOS 18, macOS 15 Sequoia, and watchOS 11.
You can configure “Private Wi-Fi address” in one of three ways:
- Off: The actual unique MAC address is sent to the router.
- Fixed: Your device generates a MAC address that’s used consistently for the selected Wi-Fi network. This may be required in some places in which a MAC address is used as part of a hotspot portal’s permission system that grants you access or in corporate environments when you’re a guest. Your home router may even offer an option to set a fixed private IP address using a MAC address, so your MAC address needs to be fixed.
- Rotating: The private address that’s generated is changed to a new, randomly created one every two weeks, whether you’re connecting in that period or after a gap of two weeks or longer.
Apple defaults to either Fixed or Rotating. It uses Fixed the first time you connect to a network with relatively modern Wi-Fi network security—WPA2 or later, to use the technical term. A network without such security, either using outdated standards or requiring no passwords, such as at an open Wi-Fi network at a café, is set to Rotating by default. You have to choose Off, read a warning, and confirm.
The options to change the type of Private Wi-Fi Address used with a network vary by operating system:
- iPhone/iPad: Go to Settings > Wi-Fi: tap the info button next to the currently connected network or any other network that appears. You can also tap Edit, and then tap the info button next to any stored network.
- Mac: Go to System Settings > Wi-Fi > Details for the active network. For other networks, click the More button; for Known Networks, then choose Network Settings.
To see the underlying Wi-Fi adapter’s hardware-set MAC address, go to Settings > General > About and look for Wi-Fi Address on an iPhone or iPad. On a Mac, follow the path of System Settings > Wi-Fi, click the Advanced button, and see Wi-Fi MAC Address near the top.
