How to Find Out My NATed IP Address

By Andrea Hamilton

All computers that are part of a network or collection of computers have a unique identifier known as an IP (Internet Protocol) address. When you have a computer or number of computers at home, you only need to have one public IP address for your router. This then acts as a gateway between your computers and the public Internet. To make the Web sites you access able to get their content back to your computer, the router does something called a NAT (Network Address Translation) to your IP address so that it is available to the public Internet. Below are the methods of locating both your IP and NATed IP addresses.

What is My IP Address?

Step 1

Open your computer's command line interface. The nature of your operating system will dictate how you do this. On Windows, click on the Start menu, select Run (or Search in Windows Vista and Windows 7) and type in "cmd" or "command." (Do not type the quotes.) Then press the return key. On a Macintosh, in the Utilities folder within Finder, you will find the Double click on this.

Step 2

Query the IP address that your computer has. On the Windows machine, type in "ipconfig" and press the return key. On a Macintosh, type in "ifconfig" and press return. Both commands will return very similar results: you will get an IP address in the form of four sets of three numbers.

Check that your IP address is similar to It will almost certainly begin with 192.168 or 10.0 These are what are known as Private IP addresses. If your IP is something totally different, check with whoever set up your home Internet router or modem to make sure that what you are seeing is correct.

What is My NAT?

Step 1

Open your favorite Web browser. You then have two options. If you know how, log on to your home Internet router or modem. This is the device that connects to the Internet via your cable connection. If you look at the interface or connection settings page, sometimes referred to as WAN (Wide Area Connection), you will see the Public IP Address. This is the address that you get "NATed" to. If you are not sure how to access your router or modem, proceed to the next step.

Step 2

Open your favorite browser and navigate to a network tools website. There are many of these and a simple online search for "Internet tools" will take you to one.

Look for a section on the home page that tells you from what IP address you are accessing the site. Failing that, look for a direct link to a page on their site that tells you the same information. This IP Address will be the one that your router or modem has, and this is the one that comes from your ISP and is the address that all your computers at home appear to be when you are surfing the web. This is your NATed IP address.