Your IP address changes automatically when your internet service provider assigns you a new one, which happens most often when you restart your modem or router, or when your lease period expires

Every device connected to the internet has an IP address — a unique number that identifies it on the network, like a mailing address for data. Your home network has one IP address visible to the outside world (your public IP), and your individual devices have private addresses used only within your home. Most home users have a dynamic IP address, which means your internet service provider does not lock you to one number permanently. Instead, they lease you an address for a set period, usually 24 hours to several months depending on your provider.

When that lease expires, or when you power-cycle your modem, your provider assigns you a different address. This happens without any action on your part — it is automatic. A smaller number of users pay for a static IP address, which stays the same indefinitely, but this costs extra and is usually only used by businesses that need a permanent address for servers or remote access.

Key Takeaways

  • Dynamic IP addresses (the standard for home internet) change automatically when your modem restarts or your lease period expires, usually every 24 hours to several months.
  • Restarting your modem is the fastest way to trigger a new IP address if you need one, though the change may take a few minutes to complete.
  • Your public IP address is visible to websites you visit, but your private IP address (used only inside your home) stays the same unless you change your router settings.
  • Static IP addresses do not change and require a paid subscription from your internet provider; they are uncommon for residential users.
  • Websites and services can see your public IP but cannot identify you personally from it alone — they would need additional information like login credentials or cookies.

What happens when you restart your modem

Restarting your modem is the most direct way to change your IP address. When you unplug the modem for 30 seconds and plug it back in, it reconnects to your internet service provider's network. During that reconnection, the provider assigns a new address from its available pool. The change usually takes two to five minutes to complete, though occasionally it can take longer.

This works because your modem is constantly leasing its IP address from your provider. The lease agreement has an expiration date built in — your provider's system tracks when that lease ends and issues a new address when the modem reconnects. Restarting the modem forces an when ready reconnection, which triggers a new lease.

If you restart your modem and your IP address does not change, it may be because your provider has a short lease renewal window, or because the new address assigned happens to be the same as the old one (rare, but possible). Waiting a few hours and restarting again usually results in a different address.

How lease expiration works

Your internet service provider assigns your IP address with an expiration date attached. This is called the DHCP lease period — DHCP is the system that hands out addresses. The lease period varies by provider: some set it to 24 hours, others to 7 days or longer. You do not see this countdown; it happens in the background.

When the lease expires, your modem automatically requests a new address the next time it communicates with the provider's network. In most cases, you will not notice this happening — your internet stays on, and the change is invisible. However, if you are running a service that depends on a fixed IP address (like a home server or security camera accessible from outside your home), the address change can break that connection temporarily.

The lease period is one reason why restarting your modem does not always produce a different IP address when ready. If your lease has only recently been issued, the provider may renew it with the same address rather than assigning a new one.

The difference between public and private IP addresses

Your home network actually uses two different IP addresses, and they work in different ways. Your public IP address is what the outside world sees — it is the address websites record when you visit them, and it is the one that changes when your modem restarts. This is the address your internet service provider assigns.

Your private IP address is used only inside your home network. Your router assigns private addresses to each of your devices — your phone, laptop, smart TV, and so on. These addresses typically start with 192.168 or 10.0 and never change unless you manually reconfigure your router. Websites cannot see your private IP address; only devices on your home network can.

When you restart your modem, your public IP changes, but your private IP addresses stay the same. Your router continues to assign the same private address to each device. This is why restarting your modem does not disrupt your home network — only your connection to the outside world changes.

When your IP address stays the same

If you have a static IP address, it does not change at all. Static addresses are permanent assignments from your internet service provider, and they cost extra — typically $10 to $20 per month depending on the provider. Most home internet users do not have static IP addresses because they are unnecessary for normal browsing.

Static addresses are used by people who need a permanent, predictable address: small business owners running a web server from home, people who need remote access to security cameras or home automation systems, or anyone else whose service depends on others knowing their IP address in advance. If you did not specifically request and pay for a static IP, you have a dynamic one.

You can check whether your address is static by restarting your modem and checking your IP address before and after. If it changes, you have dynamic IP. If it stays the same after multiple restarts, you likely have static IP, though you can confirm by calling your internet service provider.

Why websites see your IP address

Every time you visit a website, that website's server records your public IP address in its logs. This is how websites know where requests are coming from — it is a basic part of how the internet works. Your IP address alone does not reveal your identity; it is just a number. However, your internet service provider has records linking that IP address to your account, so law enforcement or a court order could connect an IP address to a specific person.

Websites use IP addresses for legitimate reasons: detecting fraud, blocking spam, managing traffic, and understanding where their visitors are located (roughly — IP addresses show city-level location, not exact coordinates). They also use IP addresses to enforce terms of service, such as blocking users who have been banned.

If you want to hide your IP address from websites, you can use a VPN (virtual private network), which routes your traffic through another server and shows that server's IP address instead of yours. However, a VPN is a separate service that requires installation and usually costs money.

How to check your current IP address

You can find your public IP address by visiting a site like whatismyipaddress.com or similar services — they display your IP when ready. You can also search "what is my IP" in any search engine and the result will appear at the top of the page.

To find your private IP address (the one your router assigned to your device), the method depends on your device. On Windows, open Command Prompt and type ipconfig, then look for "IPv4 Address" under your network adapter. On Mac, go to System Preferences > Network and select your connection. On a phone or tablet, go to Settings > Wi-Fi, tap your network, and look for the IP address listed there.

Writing down your public IP before and after restarting your modem is a straightforward way to confirm whether it changed. Most people do not need to track this, but it can be useful if you are troubleshooting a connection issue or testing whether your modem is working correctly.

Frequently Asked Questions

Can I keep the same IP address if I want one?

Yes, by purchasing a static IP address from your internet service provider. This costs extra (usually $10 to $20 per month) and locks your address permanently. Contact your provider to ask whether they offer static IP service and what the cost is in your area.

Does changing your IP address hide you from websites?

No. Websites record your IP address each time you visit, so a new address just means they see a different number. If you are logged into an account, they know it is you regardless of your IP. Hiding your IP requires a VPN or similar service, which is a separate tool.

Will restarting my modem disconnect my devices?

Yes, temporarily. When you unplug the modem, all devices lose internet connection for a few seconds. Your devices will automatically reconnect once the modem restarts, usually within two to five minutes. Your private IP addresses (the ones used inside your home) stay the same.

How often does my IP address change if I do not restart anything?

It depends on your internet service provider's lease period, which varies. Some providers set it to 24 hours, others to 7 days or longer. You can check by noting your IP address, waiting a few days, and checking again. Most home users see their address change somewhere between once a week and once a month.

Can someone find my home address from my IP address?

Not directly. Your IP address shows your general location (usually city or region), but not your street address. Only your internet service provider has records linking your IP to your home address, and they do not share that information publicly. Law enforcement can request that information with a warrant.