TL;DR
An internal (or local) IP address identifies your device within a private network and is invisible to the public internet. Assigned by a Network Address Translation (NAT) device, it differs from your external IP address, which your ISP assigns to your router for public internet access. Understanding both types helps you manage network privacy and locate your device's address across Windows, Mac, Android, and iPhone platforms.
What is an internal IP address?
Internal IP addresses designate which device in a local network is your computer, compared to other devices which might be using the intranet connection. An internal IP address is also called a local IP address. Usually, this IP address begins with 192.168. Then, after the 8, there will be a period and a final series of three unique numbers. This IP address can be seen by other devices connected to your intranet, but it cannot be seen by external devices through the internet. Your IP address is used to uniquely identify your device or network. There are specific encoding standards set by the Internet Assigned Numbers Authority (IANA) so that no two IP addresses are exactly the same, although they have similar formatting.
How are internal IP addresses assigned?
Your private or internal IP address is assigned to you by a Network Address Translation (NAT) device. Using private IP addresses reserves public or external IP addresses for, essentially, public network use. Many people currently have several devices in their homes connected to the internet, such as laptops, smart TVs, mobile phones, tablets, gaming consoles, and many others. Rather than giving each of these devices a unique external IP address to access the internet, your internet service provider (ISP) provides one external IP address to your router, which then uses internal IP addresses to connect to each of your devices.
What are the differences between internal and external IP addresses?
Generally, your internal IP address is your device's designation for your internal network, whether this is an ethernet connection or the connection between your device and your router. Your external IP address is assigned to your router by your ISP. When thinking about IP addresses, most people are concerned with their external IP address, but your internal IP address is also important. In contrast to your internal IP address, an external IP address is designated to your device by your ISP. This external IP address allows devices across the internet to find your device in order to share information, like social media updates.
| Attribute | Internal IP Address | External IP Address |
|---|---|---|
| Assigned by | Network Address Translation (NAT) device | Internet service provider (ISP) |
| Visibility | Visible only to devices on your local/internal network; cannot be seen by external devices through the internet | Visible to anyone on the internet |
| Purpose | Identifies your device within a private/local network | Allows devices across the internet to find your router/device to share information |
| Also known as | Local IP address, private IP address | Public IP address |
How does your ISP use your external IP address?
Your ISP assigns different IP addresses to the devices that log into your particular WiFi network, so they can track your internet use, including your search history and login information, and store it on their own servers. While the worst thing most ISPs do with this data is sell it to advertising companies, who use it for targeted advertising on websites and social media, this storage also makes you susceptible to data breaches if a hacker breaks into the ISP's server. However, the router you use to connect to the internet is considered part of your internal network. This router also assigns internal IP addresses to your devices when they access the router. Typically, this is the same IP address for each device rather than a unique IP address. Anyone can see your external IP address when you access the internet, but information you receive from the internet is sent through the router to your device based on your assigned internal IP address, which no one can access without breaking into your internal network. The IANA has defined these IP addresses as private or local:
- 10.0.0.0 to 10.255.255.255, a range that provides up to 16 million unique IP addresses
- 172.16.0.0 to 172.31.255.255, providing about 1 million unique IP addresses
- 192.168.0.0 to 192.168.255.255, which offers about 65,000 unique IP addresses
These are all part of Internet Protocol version 4 (IPv4), which are the most widely used IP addresses in the world. There are also some IP addresses assigned to Internet Protocol version 6 (IPv6), which you may find when you look on your computer for your IP address. However, these were issues out of concern that the world would quickly run out of unique IPv4 addresses, which has not occurred yet.
How do you find your external IP address?
One of the easiest ways to find your external IP address is, ironically, to ask the internet. Websites like WhatIsMyIP.com will ping your computer and show you both your IPv6 and IPv4 addresses. As of 2021, only the IPv4 address is relevant for most people, but IPv6 is becoming increasingly relevant. While there are many internal system differences between Windows and Apple computers, and differences between computer and mobile phone operating systems, these do not impact how you find your external IP address. You can use a search engine to find a site that will tell you your IP address, in IPv4, IPv6, or both.
How do you find your internal IP address?
Although there are simple ways to find your external IP address, different devices and operating systems have different ways for you to access your internal IP address. Here are some of the more common methods:
- Windows: To find your internal Windows IP address, open your command prompt through the Start menu. Type in "ipconfig," then hit enter. Find the line with "IPv4," which will have a number often starting with 10. If you want to always know your internal IP address, you can download an app like Rainmeter, which will display your IP address on your desktop at all times.
- Mac: On Apple computers, you can get your internal IP address by clicking the Apple icon in the top left and opening System Preferences. Next, click Network, and then, find your connection type — either WiFi or Ethernet — and click that. Usually, there will be a green dot to let you know whether this connection is active or not. Under the "Status: Connected," you should have information on your IP address, which will often start with 10. Like Windows computers, some app companies have designed programs like IP in Menubar, which you can run all the time to constantly know your internal IP address.
- Android: While there are a wide range of Android phones, from Google to Samsung, many of them have similar methods for accessing the device's internal IP address. Find "Settings," and then, select "Connections" or your equivalent. Select WiFi, as it is unlikely that your device is connected to an Ethernet connection, and then, tap the gear icon to the right of the name of your WiFi connection. This should bring up a page of information, including your internal IP address.
- iPhone: Finding the internal IP address for your iPhone is slightly different than for your Apple computer or tablet. Go to "Settings," tap "WiFi," and tap the "I" with a circle (indicating "information"), which is to the right of the network you are connected to. This should show your IP address.
Frequently asked questions
What is the difference between an internal and an external IP address?
An internal IP address identifies your device within a private or local network and is only visible to other devices on that same network; it cannot be seen by external devices through the internet. An external IP address is assigned to your router by your ISP and is visible to anyone on the internet, allowing devices across the internet to find your device in order to share information.
Who assigns my internal IP address?
A Network Address Translation (NAT) device on your local network assigns your internal IP address.
Can someone on the internet see my internal IP address?
No. Your internal IP address can be seen by other devices connected to your intranet, but it cannot be seen by external devices through the internet. Anyone can see your external IP address when you access the internet, but your internal IP address cannot be accessed without breaking into your internal network.
What are the private IP address ranges defined by IANA?
The IANA has defined the following IP address ranges as private or local: 10.0.0.0 to 10.255.255.255 (up to 16 million unique IP addresses); 172.16.0.0 to 172.31.255.255 (about 1 million unique IP addresses); and 192.168.0.0 to 192.168.255.255 (about 65,000 unique IP addresses).
How do I find my internal IP address on a Windows computer?
To find your internal Windows IP address, open your command prompt through the Start menu. Type in "ipconfig," then hit enter. Find the line with "IPv4," which will have a number often starting with 10.
What is IPv6 and why does it exist?
IPv6 stands for Internet Protocol version 6. Some IP addresses are assigned to IPv6, which was introduced out of concern that the world would quickly run out of unique IPv4 addresses. As of 2021, only the IPv4 address is relevant for most people, but IPv6 is becoming increasingly relevant.
References
Internal IP Address. (August 2020). Computer Hope.
What Is My IP Address? (July 2021). Popular Mechanics.
What Is a Private IP Address? (September 2021). LifeWire.
How to Find Your Local and External IP Address. (June 2021). LifeHacker.
