I'm using a MacBook with Bitdefender installed. When I turned the laptop on, I noticed that the IP address shown in Bitdefender was different from the one I had seen previously. A few hours later, it had changed back. One address also looked different in format, with shorter number groups than the usual address I recognize, such as 1000.12... compared with 30.32... (those aren't the real values). I'm not sure whether this was an IPv4/IPv6 difference, a VPN-related change, or a problem with my laptop. Why would an IP address change temporarily and then switch back?
4 Answers
If the VPN was active, it may have connected to a different VPN server. Each server has its own public IP, so websites can see a different address depending on which server you’re using. VPN services often choose a server automatically based on speed or availability.
There are a couple of different kinds of IP addresses involved. Your Mac has a private local address, often beginning with 192.168, 10, or 172.16, while your router has the public address that websites normally see. A VPN or Apple’s iCloud Private Relay can hide that router address and substitute another one. Also, your device may use either IPv4 or IPv6. IPv4 uses four dot-separated values, and each value can only range from 0 to 255, so an IPv4 address cannot contain a four-digit section. IPv6 addresses use hexadecimal groups separated by colons and look completely different. Seeing one format or address change is generally harmless.
That explains the different-looking address. I’ll also keep in mind that Safari may show a different public address if iCloud Private Relay is enabled.
This is normal. IP addresses are assigned by your internet provider, router, or VPN service rather than permanently belonging to the computer. Your address can change when your connection is renewed, and a VPN can also assign a different address whenever it connects to another server.
To check what websites see, temporarily disable any VPN or Private Relay feature and use an IP-checking website, then compare the result with the VPN enabled. Your ISP’s public IP may change occasionally, while VPN addresses can change much more often. Nothing here suggests that the Mac’s network hardware is defective.
The VPN itself wasn’t intentionally running; Bitdefender was simply displaying an IP address in its interface. Either way, it’s reassuring to know that the change doesn’t necessarily indicate a problem.