What is an IP address?
A plain explanation of the number every device uses online, and what it reveals about you.
An IP address is a number that identifies a device on a network. Whenever you open a website, send a message, or stream a video, your device sends small packets of data across the internet, and each packet carries your IP address so the reply knows where to come back to.
The easiest way to picture it is a return address on an envelope. The website you visit needs it to send the page back to you, the same way a letter needs a return address to be answered.
What an IP address looks like
Most IP addresses you'll see are IPv4 addresses: four numbers between 0 and 255, separated by dots, such as 203.0.113.42. Newer IPv6 addresses are longer and use letters and numbers separated by colons, such as 2001:db8:85a3::8a2e:370:7334. Our guide to IPv4 vs IPv6 explains why both exist.
Who gives you an IP address?
Your internet provider assigns your public IP address, the one websites see. At home, it belongs to your router, and every device on your Wi-Fi shares it. Inside your home, your router gives each device its own private address, which is why your laptop and phone show different numbers in their settings. See public vs private IP addresses.
Most home connections get a dynamic address, which can change from time to time, for example when your router restarts. Businesses that host servers often pay for a static address that never changes.
What your IP address reveals
- Your internet provider, such as the company that runs your broadband or mobile network.
- An approximate location, usually your country and often your city or region. This comes from databases that track where providers use their addresses, so it can be off by many kilometres.
It does not reveal your name, your email, or your street address. Your internet provider can link an address to a customer account at a given time, but they don't share that publicly. In many countries they only release it under legal processes such as a court order.
Why websites care about your IP
Sites use your IP to send you data, to show content for your country, to slow down spam and repeated login attempts, and to estimate where their visitors come from. Streaming services also use it to decide which catalogue you're allowed to see.
Last updated October 2026.