How to Find Your IP Address

Networks, and the internet, don’t identify computers (of any size, even your smartphone) by the name you give them. Computers prefer numbers, and the numbers they use as identifiers are called IP addresses.

The “IP” stands for “internet protocol,” which is part of Transmission Control Protocol/internet Protocol (TPC/IP). It’s all called IP for short, and TCP/IP is the language used for communication by most networks.

When it comes to your computer(s), there are actually several IP addresses involved. One is how the computer talks to the internet at large, which is the IP address of your router. That IP address is generally assigned to the router by your internet service provider (ISP); the router, in turn, handles all the traffic from your computer out to the internet. So even though a website only sees a request come in from the IP address on the router, the router knows how to route the information to/from the computer. (That’s why it’s called a router.)

Computers on the internal networks, be it Wi-Fi or Ethernet, at home or in the office, have their own IP addresses assigned to them (usually by the router). That way, all the nodes on the internal network can also communicate. The protocol used by the router to assign IP addresses is called Dynamic Host Control Protocol (DHCP).

If you have an IP address assigned, it’s typically considered a “dynamic IP” because it could be temporary; the router might give the node in question a different IP address at a later time (same with the IP address your ISP gives your router). However, you can set up “static IP addresses” on computers so they never change—this can be important for some kinds of network communications, especially if it’s crucial to be able to find that same node over and over. You could also get a static IP for your router—which is handy if you run a web server, for example, but expect your ISP to charge extra.

IP addresses are typically in the same format as a 32-bit number, shown as four decimal numbers each with a range of 0 to 255, separated by dots—each set of three numbers is called an octet. This format is used by IP version 4 (or IPv4). With it, you could—in theory—have 0.0.0.0 to 255.255.255.255 out there. However, this limited the world to a possible 4+ billion IP addresses, which isn’t enough.

So now, there’s IPv6, which is 128-bit, and went from four to 16 octets. That’s a lot more than 4 billion—it’s a 34 with 37 zeros after it (or 2 to the 128^th power). Technically, 340,282,366,920,938,463,463,374,607,431,768,211,455. That’s a lot of IP addresses.

That’s all good to know, but how do you find your IP address?

Find Your Internet/Public IP Address

There may come a time when you need to know the IP address of your router, as assigned by your ISP. This can be particularly handy for things like VoIP calls or remote control software.

What you’ll also find is that there’s lots of information about you attached to that IP address, specifically your ISP’s name and your general location (called a GeoIP). That’s because ISPs dole out a range of IP addresses. Figuring out your provider and general location based on IP address is as simple as consulting a public list.

The simplest way to check your router’s public IP address is to search “what is my IP?” on Google.

With Google, that’s all you see. There are plenty of sites out there that will show you the exact same thing. They see it simply because by visiting the site, your router has made a request, and thus revealed the IP address. Sites like WhatIsMyIP.com and IPLocation all go farther, showing off the names of your ISP, your city, and even maps.

The GeoIP info is far from foolproof. Generally, you’re going to get an approximation of…