Public IP vs. Private IP Address: What’s the Difference and Why It Matters

Diagram comparing public and private IP addresses: local devices use private IPs via a router, which connects to the internet through a single public IP from an ISP.

Have you ever looked up your IP address on a tool like WhatIsMyIPAddress.com’s tool and noticed what looks like a discrepancy? You may notice that the lookup tool says one IP address when you check on your phone, but you see another when you look at your router settings.

There’s a reason for that, and it’s actually really useful to understand!

Your device doesn’t just operate with one IP address. It uses a private IP within your home network, while your network shares a public IP with the internet. They serve different purposes, and they’re assigned by completely different sources.

Once you understand how the two types work together, a lot of things start to make more sense. That’s why your neighbor’s network shows a different address than yours, why a VPN changes what websites see but not your local network setup, and what it actually means for your privacy.

Why 2 IP Addresses? The Short Answer

What is a Private IP Address?

What is a Public IP Address?

How Public and Private IP Addresses Work Together

How to Find Both Your Public and Private IP Address

Why 2 IP Addresses? The Short Answer

Every device that connects to the internet operates using two IP addresses, not one. There’s a private IP address, which exists only within a private network, and a public IP address, which is what the rest of the internet sees when you browse, stream, or send an email.

A simple analogy is that your private IP address is like your apartment number, identifying your specific unit within a building. However, that doesn’t mean anything to someone who doesn’t know your street address. If someone knows that you live in apartment 32, but they have no idea what building you’re in, that unit 32 knowledge doesn’t mean much.

Your public IP address, on the other hand, is like your building’s street address. That’s how the outside world finds you.

Both numbers are necessary, but they operate in completely different contexts.

Your Internet Service Provider (ISP) assigns your public IP address, which is typically shared across every device in your home. Your router handles the private side, giving each device on your network its own internal address to keep traffic organized. Your laptop, your phone, your smart TV, and your smart thermostat can all have different private IP addresses while sharing the same public one.

That separation between public and private IP addresses is intentional. It’s what makes home networking work.

What is a Private IP Address?

A private, internal IP address is assigned to each device on a private network by that network’s router. This is only used within your network, which means it’s not routable on the public internet.

On your home network, every internet-connected device receives its own private IP address. That allows your router to tell each device apart and send the right data to the right device. Without this system, your router would have no way of knowing whether the Netflix show you’re streaming belongs to your TV, your tablet, or your phone.

All of this is handled automatically by a system called DHCP (Dynamic Host Configuration Protocol). Your router has a pool of reserved private IP ranges from which it can assign numerous devices. You don’t have to do anything because the router manages it in the background every time a device connects to this network.

You might recognize one of the number ranges that has been set aside strictly for internal network use: 192.168.x.x, the default private network. You may also see 10.x.x.x, which is common in larger networks like offices or schools, or 172.16.x.x through 172.31.x.x, which is less common but still reserved for private use. If you’ve ever poked around in your router settings and seen an address starting with one of those ranges, you’re looking at a private IP.

The reason every device on your network can have its own private address without causing conflicts is that these ranges are intentionally kept off the public internet. Two households across the street from each other can both have a device assigned 192.168.1.5 without any problem, because those addresses never leave the local network. They’re essentially invisible to the outside world, which contributes to a basic layer of network privacy.

A public IP address identifies a network’s connection to the internet.

What is a Public IP Address?

In contrast with the private IP address that helps your network manage all the devices on your private network, a public IP address identifies your network connection to the rest of the internet.

Any time you visit a website, check your email, or stream a video, the servers handling those requests see your public IP address. That’s how they know where to send the information to.

Your public IP address is assigned by your ISP to your internet connection, not to any specific device. Every device in your home, then, shares the same public IP address when communicating with the outside world. Even though your laptop and your phone may have different private IP addresses, they’re still going to show the same public address.

Your laptop and your partner’s phone may have different private addresses, but to a website you both visit, you’re coming from the same place.

Most home internet customers have what’s called a dynamic public IP address, meaning it can change periodically. Your ISP pulls it from a pool and may reassign it when you restart your modem or on a set schedule. Some ISPs offer a static public IP address that stays the same permanently, which is useful if you’re hosting a website or need consistent remote access to your home network. For most everyday users, dynamic is the default and works just fine.

How Public and Private IP Addresses Work Together

When you open a webpage, both your private and public IP addresses are involved in making sure it loads the way you expect it to. The handoff between public and private IP addresses happens in a fraction of a second, without you ever noticing.

Here’s what happens: When you type any address into a web browser, your device sends the request to your router over your local network using its private IP address, then forwards the request to the internet, using the public IP address.

When the website receives the request, it sees your public IP and sends the page data back to it. Your router, then, delivers the data to the right device on your network. This whole round trip? It can happen in milliseconds?

The system that makes this possible is called NAT, or Network Address Translation. This system translates between your single public IP address and the many private ones on your network. It’s also why the terms “internal IP address” and “external IP address” mean the same thing as private and public. Internal refers to what’s happening inside your network, whereas external refers to what’s visible outside of it.

If you’re in a conversation with tech support and they ask for your external IP, they’re asking for the public one. For an internal IP, they want the private address that is assigned to your device.

Hands holding a laptop while locating the private IP address in system settings.

How to Find Both Your Public and Private IP Address

Finding either address takes less than a minute, and it’s worth knowing how to do both.

Your public IP address is the easier one to find. Head to the WhatIsMyIPAddress.com /homepage, and it will display your current public IP address automatically, along with your ISP, city, and region. There’s no setup required!

Finding your private IP address depends on your device:

On a Windows computer, open the Start menu, search for “Command Prompt,” and type: ipconfig. Look for the line that says “IPv4 Address” under your active network connection.
On a Mac, go to System Settings, select Network, choose your active connection, and your IP address will be listed there.
On an iPhone, open Settings, tap Wi-Fi, and tap the network you’re connected to. Your private IP address appears under the IPv4 Address section.
On Android, the path varies slightly by manufacturer, but you can generally find it in Settings under Wi-Fi, then tapping your connected network for details.

If you want to see all the devices connected to your network and their private IP addresses, logging into your router’s admin panel is the most complete way to do that. You can usually access it by typing 192.168.1.1 or 192.168.0.1 into your browser’s address bar.