Guide
What is an IP address?
Every device on the internet has an address that tells data where to go. Here is what that address is, where it comes from and what it says about you.
An IP address (Internet Protocol address) is a number that identifies a device on a network. When you open a website, your request carries your IP address as the return address, so the website’s server knows where to send the page. Without it, data on the internet would have nowhere to go.
You can see the public IP address you are using right now on the IPLookr homepage.
What an IP address looks like
There are two versions in use today:
- IPv4, four numbers from 0 to 255 separated by dots, such as
203.0.113.42. There are about 4.3 billion of them, fewer than the number of devices online. - IPv6, eight groups of hexadecimal digits separated by colons, such as
2001:db8::8a2e:370:7334, where::stands for a run of zeros. There are so many that they will never run out.
Our guide to IPv4 vs IPv6 explains the differences.
Where IP addresses come from
IP addresses are handed out in layers. IANA, the Internet Assigned Numbers Authority, manages the global pool and gives large blocks to five Regional Internet Registries: ARIN for North America, RIPE NCC for Europe, the Middle East and Central Asia, APNIC for Asia-Pacific, LACNIC for Latin America and AFRINIC for Africa. They assign blocks to internet providers and large organizations, and your provider assigns an address to your connection.
Public and private addresses
Your router has a public IP address on the internet. The devices at home get private addresses, such as 192.168.1.20, which only work inside your network. The router translates between the two, so all your devices share one public address. Read more in public vs private IP addresses.
What your IP address reveals
- Your internet provider, or the organization that owns the network.
- A rough location, usually the country and often the region or city. City guesses are frequently wrong, and the location is that of your provider’s network, not your home.
- Not your name or street address. Only your provider can link an address to a customer, and it normally does so only when legally required.
Websites still use IP addresses to estimate your country for language and prices, to block abuse, and sometimes to track visitors. If you’d rather not share yours, see how to hide your IP address.
IP addresses and domain names
People remember names like example.com; computers need numbers. The Domain Name System (DNS) works like a phone book that turns names into IP addresses. To go the other way and see who an address belongs to, use the IP lookup.
Frequently asked questions
Can someone find my home address from my IP address?
No. An IP address points to your internet provider and a rough area, usually a city or region, and often not even that accurately. Only your provider knows which customer used an address at a given time, and it normally shares that only when legally required.
Does my IP address change?
Usually, yes. Most home and mobile connections get a dynamic address that can change when the router restarts or the provider reassigns addresses. A static address that never changes is mostly used by businesses and often costs extra.
Is an IP address the same as a MAC address?
No. A MAC address is built into a network adapter and only matters on your local network. An IP address is what lets data find its way across the internet, and it depends on where you connect from.
Can two devices have the same IP address?
Within one network, no. But all the devices in a home usually share one public address towards the internet, and the private addresses inside, like 192.168.1.20, are reused in millions of homes at once.