What Is an IP Address?

An IP address (Internet Protocol address) is a numerical identifier used to identify and communicate with devices or network connections using the Internet Protocol. In simple terms, it is a number that lets data find its way to the right place on a network, including the internet.

This guide explains how IP addresses work, how the two versions differ, what an IP address can and cannot reveal about you, and how to look up your own.

How Does an IP Address Work?

Whenever you load a web page, stream a video, or send a message, your data travels across many networks in small pieces called packets. Each packet carries the IP address it came from and the IP address it is going to. Routers along the way read the destination address and pass the packet toward the right network until it arrives.

A common analogy is a mailing address. A letter needs a destination address to be delivered, and a return address so a reply can come back. An IP address plays a similar role for internet traffic. This is only an analogy: an IP address identifies a network connection, not a person, and it is not a street address.

An IP address often identifies the connection a device is using rather than the device itself. If you move your laptop from home Wi-Fi to a café, the device is the same, but it is now using a different connection and usually a different IP address.

IPv4 vs IPv6

There are two versions of the Internet Protocol in everyday use, and both are in use on the internet today.

IPv4

IPv4 addresses are 32 bits long and are usually written as four numbers from 0 to 255 separated by dots, for example 192.0.2.1. A 32-bit address allows roughly 4.3 billion unique values, which turned out to be too few for the number of devices that want to be online.

IPv6

IPv6 addresses are 128 bits long and are written as groups of hexadecimal digits separated by colons, for example 2001:db8::1. The double colon is a shortcut for one or more groups of zeros. IPv6 provides a vastly larger address space than IPv4, large enough that running out is not a practical concern.

The two example addresses above come from ranges reserved for documentation, so they are safe to use in examples and do not belong to a real connection.

Both are used today

IPv6 has not replaced IPv4. Many networks support both at once, some connections have only IPv4, and some have both. Because of this, you may see an IPv4 address, an IPv6 address, or both when you check your connection. Not having IPv6 is common and usually does not stop websites from working.

Public vs Private IP Addresses

A public IP address is the address your connection uses to communicate across the public internet. It is the address websites and online services see when you connect to them.

A private IP address is used inside a local network, such as your home or office. Private addresses are not routed across the public internet, so many different networks can reuse the same ones. The common IPv4 private ranges are:

• 10.0.0.0/8
• 172.16.0.0/12
• 192.168.0.0/16

At home, your router usually has one public IPv4 address from your ISP, and your phone, laptop, and TV each get a private address from the router. A technique called network address translation (NAT) lets all of those devices share the single public IPv4 address when they reach the internet. That is why the address you see on a lookup page is often not the one shown in your device's network settings.

Static vs Dynamic IP Addresses

A static IP address is one that is assigned consistently and generally stays the same. A dynamic IP address can change over time and is commonly assigned automatically by an ISP or network.

Many home connections use dynamic addresses, while static addresses are often used for servers or offered as an option by some providers. Policies differ between ISPs and networks, so one provider's approach should not be assumed to apply to another.

What Can Your IP Address Reveal?

Services can look up an IP address in databases and may be able to estimate information such as:

• The ISP or network provider
• The approximate country
• The approximate region
• The approximate city
• Network information, such as the autonomous system number (ASN)

An IP address generally does not reveal your exact home address or precise physical location by itself. IP geolocation is an estimate, and it can be wrong. It may point to a nearby city, the location of your ISP, a network gateway, or another approximate area, and the data can be outdated or incomplete. Treat any IP-based location as a rough guide, not a precise position.

Can Your IP Address Change?

Yes, it can. Common reasons include:

• Reconnecting to your ISP, for example after restarting your router
• Your ISP reassigning addresses
• Switching between Wi-Fi and mobile data
• Using a VPN
• Moving to a different network, such as public Wi-Fi at a café or hotel

How often this happens depends on your network and your ISP. Some connections keep the same address for a long time, while others change more often.

Does a VPN Change Your IP Address?

Usually, yes. When your traffic is routed through a VPN, websites normally see the VPN server's public IP address instead of your usual one. Your device and your normal connection are still there, but the address visible to the sites you visit is the VPN's.

That is all this tells you. A VPN does not guarantee privacy or security on its own, and results depend on the provider and your settings. Detecting whether an address belongs to a VPN or proxy is also imperfect, because it relies on network signals and third-party data. Such checks can produce false positives and false negatives and are not 100% accurate.

How to Find Your Public IP Address

The simplest way is to use an IP lookup tool. WhatIsMyIP shows your current public IPv4 and IPv6 address when available, along with network information such as your ISP and an approximate location. You can read more about the site on the About page.

Check your IP address

Your device's network settings usually show your private address instead, which is different from the public address that websites see.

Why Do Websites See Your IP Address?

Internet communication works by sending requests and receiving replies. When your browser asks a server for a page, the server needs to know where to send the response, and the IP address of the connection that made the request is how it does that. Without it, the reply would have nowhere to go.

This is part of how the internet works, not something unusual. It also means the address a website sees is normally the public address of your connection, which may belong to your home router, a mobile network, or a VPN server.

Is an IP Address Personal Information?

It depends. How an IP address is treated can vary with the context in which it is used and with applicable privacy laws, and rules differ between countries and regions. On its own, an IP address identifies a connection rather than naming a person, but in some situations it can be linked to an individual, which is why it is often handled with care. This is general information, not legal advice.

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