What Is an IP Address? A Plain-English Guide

An IP address (Internet Protocol address) is a number that identifies a device or network on the internet, so data knows where to go and where it came from. Think of it as the return address on a letter. Without one, a website would have nowhere to send the page you asked for.

What an IP address looks like

There are two formats in use today. An IPv4 address is four numbers separated by dots, such as 203.0.113.42. An IPv6 address is longer and written in hexadecimal, such as 2001:db8:85a3::8a2e:370:7334. Both do the same job. If you want the details, read IPv4 vs IPv6.

What an IP address is used for

• Routing. Routers read the destination address on every packet and pass it along until it arrives.
• Identifying a network. Servers see the address your traffic comes from and send the reply back to it.
• Rough location. Services use IP databases to guess your country or city, for language, currency or content licensing.
• Security. Sites use addresses to rate-limit abuse, block bad actors and allow-list trusted ones.

Public and private addresses

Your home has one public IP address that the rest of the internet sees, and every device inside it has a private address that only works on your local network. Your router translates between the two. We explain this in public vs private IP addresses.

How you get an IP address

Your internet service provider assigns the public address, usually automatically through a system called DHCP. Most home connections receive a dynamic address that can change over time, while businesses often pay for a static one that never does. See why your IP address keeps changing.

What your IP address reveals about you

A public IP address typically reveals your internet provider, your country and often your city or region. It does not reveal your name, your street address or what you do online. Anyone who wants to connect an address to a person normally needs your provider's records, which are released only through legal process. For a fuller answer, read can someone track you by your IP address?

How to find your IP address

Your public IP address is the one at the top of our home page. For every device and operating system, see how to find your IP address. To find the private address of a device on your network:

• Windows: open Command Prompt and run ipconfig.
• macOS: open System Settings, choose Network and select your connection.
• Linux: run ip addr in a terminal.
• iPhone or Android: open the Wi-Fi settings and tap your network.