Key Takeaway:
“My IP keeps changing” can mean three different addresses: the public one websites see, which your provider lends you; the local one your router gives each device; and your IPv6 address, which modern systems deliberately change about once a day for privacy. All three changing is normal and none of it means you’ve been hacked. Work out which one is changing, then decide whether it matters for what you’re doing.
Most people notice this when something breaks: a game server or a camera can’t be reached from outside, a site keeps asking you to verify your login, or a work system that allows only certain addresses suddenly locks you out. The fix depends entirely on which address moved.
First: Which Address Is Changing?
| Address | Who gives it to you | How to see it |
|---|---|---|
| Public IPv4 (e.g. 203.0.113.25) | Your internet provider | What Is My IP |
| Local IPv4 (e.g. 192.168.1.23) | Your router | ipconfig on Windows, Wi-Fi details on phones and Macs |
| IPv6 (e.g. 2001:db8::1a2b) | Your device builds it from a prefix your provider gives your router | IPv6 test |
Write down all three, then check again tomorrow, or after a router restart. The free lesson Find Your IP Addresses shows where each one lives on every kind of device.
Why Your Public IP Changes
Most home connections have a dynamic public address. Your provider lends it to your router for a period, called a lease, from a pool shared with other customers. Whether you get the same one back depends on the provider. Common reasons it changes:
- Your router or modem restarts, after a power cut, a firmware update or because you rebooted it. Some providers hand back the same address; others give you a new one each time.
- The lease runs out while the router is off, or the provider reorganises its address pools during maintenance.
- You’re on mobile data. Mobile networks often give you a different public address with each new data session, and many customers share each one through a system called CGNAT. Moving between masts, switching flight mode on and off, or the phone waking up can all bring a new address.
- A VPN or privacy relay is on. Sites then see the VPN server’s address, which changes whenever you change server, reconnect, or the app picks a new one for you.
- You changed network, for example from home Wi-Fi to the office, a café or your phone’s hotspot. Each network has its own public address.
If you need an address that never changes, that’s a static IP, and only your provider can give you one, usually for a fee. Our guide to dynamic vs static IP addresses explains when that’s worth paying for and when the free alternative, dynamic DNS, does the job.
Why Your Local IP Changes
Inside your home, your router lends local addresses in the same way, using DHCP. A device often gets the same one back, but not always. Two things make it change more than people expect:
- Private Wi-Fi addresses. Phones and laptops now hide their real hardware (MAC) address from networks. Android 10 and later use a randomised address by default, normally the same one for each network. On Apple devices with iOS 18 or macOS Sequoia 15 and later, the Private Wi-Fi Address setting can be Off, Fixed or Rotating. When the device presents a new hardware address, the router treats it as a new device and may give it a different local IP. Forgetting and rejoining a network can have the same effect.
- The router restarted or its list filled up. After a reboot, or when lots of devices come and go, a router may hand addresses out in a different order.
This matters for port forwarding, printers and anything else you’ve pointed at a specific local address. The fix is a DHCP reservation (sometimes called a static lease) in your router, which ties one address to one device. If the device uses a rotating private address, set that network to a fixed address first, or the router won’t recognise it. You can check whether a device is showing its real hardware address or a private one with our MAC address lookup.
Why Your IPv6 Address Changes Every Day
This one is deliberate. If your device kept one IPv6 address forever, every site could recognise it wherever it went. So modern systems create temporary addresses with random endings and replace them regularly, an approach set out in RFC 8981. On Windows 11, netsh interface ipv6 show privacy shows the defaults: temporary addresses on, each one preferred for at most a day and kept for at most seven days. That’s also why a device can show several IPv6 addresses at once: older ones stay valid for a while after a new one takes over.
The front half of the address, the prefix, comes from your provider and changes too if your provider changes it, often when the router reconnects. Our IPv6 test shows your current address and checks that it isn’t built from your hardware serial number. For the bigger picture, see what IPv6 is.
Does It Matter?
For browsing, streaming and gaming as a player, no. It matters in a handful of situations:
- Reaching your home from outside: a camera, a game or media server, remote desktop. Use dynamic DNS, a fixed name that follows your changing address, or a remote-access tool that doesn’t need open ports at all.
- Allowlists: work systems, website admin panels or databases that only accept certain addresses. Ask whether they can allow a VPN with a fixed address, or your provider’s static IP.
- Repeated security checks: some services ask you to verify your login when your address changes, especially if it jumps between countries because of a VPN.
- Shared reputation: on mobile data or CGNAT you share an address with strangers, so an address someone else misused can get you CAPTCHAs or blocks. Check any address with our IP reputation checker.
A changing address is also a small privacy plus: it makes it harder to link your activity over long periods by address alone. See what your IP address reveals.
How to Get a New IP, or Keep the One You Have
To get a new public IP: restart the modem or router and check again. If you get the same address, your provider is keeping it for you, and leaving the router off for longer sometimes helps. Switching to mobile data or a VPN changes it immediately. Our guide to changing your IP address covers every method.
To keep it stable: for the public address, ask your provider for a static IP, or use dynamic DNS. For local addresses, set a DHCP reservation in your router. For IPv6, leave temporary addresses on: devices that need a fixed address, like a home server, can have one alongside the temporary ones.
Frequently Asked Questions
Does a changing IP address mean I’ve been hacked?
No. Addresses change because providers, routers and operating systems are designed to change them. Signs of a real problem look different: unknown devices on your network, router settings you didn’t make, or DNS servers you don’t recognise. Our free course Secure Your Home Network shows how to check.
Why does my phone’s IP change so often?
On mobile data, the network can give you a new public address each time a data session starts, and phones start new sessions often. On Wi-Fi, a private Wi-Fi address can also give the phone a new local address on each network.
Why is the IP in my router different from the one websites see?
Either a VPN is on, or your provider uses CGNAT. If the router’s internet (WAN) address starts with 100.64 to 100.127, you’re sharing a public address with other customers. See what CGNAT is.
How often do home IP addresses change?
It depends on your provider. Some keep the same address for months unless the router is off for a long time; others change it at every reconnection. Keep a note of yours for a couple of weeks to see your provider’s pattern.