What Is My IP Address? A Complete Guide

Every device on the internet has an address. When you load a website, send an email, or stream a video, packets of data are stamped with where they came from and where they're going. That stamp is the IP address.

If you've ever typed "what is my IP" into a search bar, you've already used a tool to ask a server: what address are my packets coming from right now? The answer it returns is your public IP address — and there's a lot you can learn from it, but also a lot it doesn't tell.

This guide walks through what an IP address actually is, why most people see two different ones depending on where they look, what websites can do with the address they see, and what stays hidden.

What an IP address actually is

An IP address is a numerical label. Computers route data using these numbers the way a postal system uses ZIP codes — every packet on the internet has a source address and a destination address, and routers along the way use those numbers to decide which way to send it.

The familiar dotted-quad form looks like 8.8.8.8 or 192.168.1.1. That's an IPv4 address — four numbers, each between 0 and 255, separated by dots. Under the hood it's actually a 32-bit number; the dots are just for human readability.

You don't think about IP addresses most of the time because DNS translates names to numbers automatically. When you type github.com, your computer asks a DNS server "what's the IP for github.com?" and gets back something like 140.82.112.3. The connection is made to that number. The name was just for you.

Public IP vs private IP

Here's where most people get confused. If you check your computer's network settings, you'll likely see an address like 192.168.1.42 or 10.0.0.5. Then you visit a "what's my IP" site and it shows something completely different — maybe 73.16.224.18. Both are real. They serve different purposes.

The address on your computer is a private IP. Three ranges of IP addresses are reserved by convention for private networks: 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. These addresses can be used freely on any local network — your home, your office, every coffee shop — because they never appear on the public internet.

What the world sees is your public IP, the address assigned to your router by your ISP. Your router translates between the two using a process called NAT (network address translation). Outgoing packets from your laptop, phone, and TV all leave your network with the same public IP — your router keeps track of which device asked for what, so when responses come back it knows where to forward them.

This is why a single home with a dozen connected devices uses one public IP, and why your apparent location to a website is your router's location, not your laptop's.

IPv4 vs IPv6

The IPv4 system has about 4.3 billion addresses. That sounds like a lot, but the internet ran out of fresh ones around 2011 — every smartphone, IoT device, and server competes for the same pool. IPv6 was introduced to fix this: it uses 128-bit addresses instead of 32-bit, giving roughly 340 undecillion possible addresses. Practically infinite.

An IPv6 address looks like 2001:0db8:85a3:0000:0000:8a2e:0370:7334, often shortened by collapsing zeros to 2001:db8:85a3::8a2e:370:7334. Eight groups of hex digits separated by colons. They're harder to remember, but you almost never need to.

Most modern networks run dual-stack — both IPv4 and IPv6 active at the same time — and clients prefer IPv6 when both are available. If you check your IP and see two values, that's why. To understand the size of any IP block in either version, you can paste a CIDR like 2001:db8::/32 into our CIDR calculator.

What websites can see

When you visit a site, the server sees your public IP because it has to — without it, there's no way to send the response back. From that one number, a few things follow:

• Approximate geographic location. IP geolocation databases map address ranges to cities, regions, and countries. Accuracy varies wildly: country-level is usually right, city-level is often right, anything more precise (a street, a neighbourhood) is almost certainly wrong.
• Your ISP. The address belongs to a block owned by your internet provider, and registries like RIPE and ARIN make this public.
• The autonomous system number (ASN). A routing identifier — every block of IPs is announced to the global routing table by some ASN, and that's almost always the ISP or a hosting company.
• Whether you're on a known VPN, proxy, Tor exit, or data centre. Specialised databases track which IP ranges belong to commercial VPNs and hosting providers.

What a site cannot see from your IP alone: your name, your exact home address, your phone number, what's installed on your computer, or what other tabs you have open. Those would require additional information — cookies, fingerprinting scripts, or you signing in to an account.

Why your IP changes

Most home internet connections use dynamic IPs, meaning your ISP assigns you an address from a pool when you connect, and may change it later. Sometimes "later" means every reboot of your router. Sometimes it means every few months. The IP you see today may not be the IP you have tomorrow.

Static IPs don't change — they're assigned to you permanently. Businesses pay for them so their services stay reachable at a fixed address. ISPs typically charge extra for static IPs at home, and most consumers don't need them.

Mobile networks change your IP even more often, because devices move between cell towers and reconnect frequently. If you check your IP on cellular data twice in five minutes, you might see two different values.

What you can hide, and what you can't

If you don't want a website to see your real IP, you have to put something between you and the site. There are two common options.

A VPN routes your traffic through a server you choose. The website then sees the VPN server's IP, not yours. Quality VPN services are widely available; quality varies, and free VPNs in particular often have business models that involve selling your data, so be deliberate about which one you trust.

Tor routes your connection through three random volunteer-run relays, with each relay only knowing the previous and next hop in the chain. Sites see the IP of the final "exit node", which has no relationship to you. Tor is slower but offers stronger anonymity by design.

What neither hides: traffic patterns, browser fingerprinting, and anything you voluntarily disclose. A VPN protects your IP from a site, but if you sign in to your account afterwards, the site knows who you are anyway.