What Is an IP Address?

Every device on the internet has one. Here's what an IP address actually is, what it reveals about you, and why it matters — in plain English.

The short answer

An IP (Internet Protocol) address is a unique number that identifies a device on a network. Think of it as a mailing address for data: when you open a website, your device sends a request stamped with your IP address, and the server uses it to send the page back to the right place.

Public vs private IP addresses

You actually have two IP addresses at any given moment:

  • Public IP — assigned by your internet provider to your router. This is the address the entire internet sees. It's what this site shows you.
  • Private IP — assigned by your router to each device in your home (phone, laptop, TV). These usually look like 192.168.1.x or 10.0.0.x and are invisible to the outside world.

Your router performs NAT (Network Address Translation), letting many devices share one public IP — which is why your phone and laptop show the same public address on Wi-Fi.

Dynamic vs static IP addresses

Most home users get a dynamic IP: your ISP assigns it temporarily and may change it when your modem reconnects. A static IP never changes — useful for hosting servers or remote access, and usually costs extra.

What does your IP reveal?

From your IP alone, anyone can typically learn:

  • Your approximate location — usually the city or region, not your street
  • Your internet provider (ISP)
  • Whether you're on a residential, mobile, business, or datacenter connection

What it cannot reveal: your name, exact address, or browsing history. Only your ISP can map an IP to a subscriber, and normally only under a legal order. Still, advertisers and websites use IPs for rough geo-targeting — if you'd rather not share it, see how to hide your IP address.

IPv4 and IPv6

There are two versions of IP in use today. IPv4 addresses look like 203.0.113.42 and are nearly exhausted; IPv6 addresses look like 2001:db8::8a2e:370:7334 and are effectively unlimited. Read the full comparison in our IPv4 vs IPv6 guide.

How to check your IP

Just visit checkpublicip.com — your public IP appears instantly at the top of the page, along with your ISP, location, and browser details. From a terminal, run curl checkpublicip.com.