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What is my IP address, and why does it matter?

Your public IP is the address the rest of the internet uses to talk to you. Here's what it reveals, what it doesn't, and how to check it.

Your public IP address is the one the rest of the internet sees when you make a request. It's how servers know where to send their replies. Unlike a private address (like 192.168.1.x or 10.0.0.x), your public IP is unique — globally — and tied to your network provider.

What your IP reveals

Three things, broadly:

  • Your ISP (Internet Service Provider). Whoever issued the IP.
  • Your approximate geographic location — usually city-level, sometimes country or zip. Used by every ad network for "geo-targeting."
  • Your network type — residential broadband, mobile, hosting, VPN exit node, Tor exit, etc. There are databases that fingerprint each.

What it does not reveal: your name, your exact address, your device, or what you're doing. It's not personally identifiable on its own — but it can be combined with logs from sites you visit to build a profile.

IPv4 vs. IPv6

Most people have both. Your ISP assigns you one IPv4 address (because we're running out) and one or more IPv6 addresses (because we're not). Many sites still only support IPv4, but a growing number support IPv6 — and you'll get a different IP depending on which protocol you use.

Our What Is My IP tool shows you both, plus the reverse DNS (PTR record) and approximate geolocation.

Why your IP "leaks" even with a VPN

Common ways your real IP leaks past a VPN:

  • WebRTC in your browser. It's a real-time communication protocol that exposes local network interfaces, and it can bypass your VPN tunnel in some browsers.
  • DNS leaks. If your computer is still using your ISP's DNS servers instead of your VPN's, every domain you look up is observable by your ISP.
  • IPv6 leaks. Your VPN might tunnel IPv4 only. If your network is dual-stack, IPv6 traffic bypasses the tunnel.
  • Torrent clients. They announce your IP to every other peer in the swarm.

Static vs. dynamic

Most residential ISPs assign dynamic IPs — your address can change when your lease expires, when the modem reboots, or whenever the ISP feels like it. Some ISPs (and most business connections) offer static IPs that never change.

If you run a server at home, you almost certainly need a static IP — or a dynamic DNS service like No-IP that updates a DNS record whenever your IP changes.

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