What is an IP address?

An IP address is a number that identifies a device — or, more often, a whole home network — on a network. The internet uses it the way postal mail uses a street address: to send replies back to you. You can see your public IP without installing anything. SpeedMetric does not store it.

Public vs private IP

Your laptop on Wi-Fi almost always has a private address, commonly in 192.168.x.x, 10.x.x.x or 172.16–31.x.x. Those ranges stay inside your home or office. The router then shares one public IP with the rest of the internet. Websites, speed tests and mail servers see the public address, not the 192.168 address printed in your Wi-Fi settings.

Some mobile and home ISPs put many customers behind carrier-grade NAT (CGNAT). You still have a private address at home; the public address is shared. That does not make a speed test invalid, but it can complicate hosting a game server or inbound connections.

IPv4 vs IPv6

IPv4 looks like 203.0.113.10. The world ran short of those 32-bit numbers, so IPv6 uses longer hexadecimal addresses such as 2001:db8::1. Many connections have both (dual-stack). Neither version is automatically faster; download, upload and ping still depend on the path, not the address format. If the lookup page shows IPv6, your ISP has given you a v6 path to this site.

Dynamic vs static

Most residential public IPs are dynamic: the ISP can assign a new one when the modem reconnects. A static IP stays the same and is usually a paid extra for servers. A changing IP is normal and is not a sign that your speed dropped.

IP, privacy and this site

Any website you visit can see the public IP of the request — that is how the internet routes packets. SpeedMetric uses it to run the test and to show it back to you if you ask. We do not sell it or build a lasting profile. See the privacy policy and the FAQ for how the tools treat connection data. Advertising, when present, is described there as well; ads do not change the address the lookup shows.

What an IP is not

An IP address is not a speed rating, a Wi-Fi password, or a home street address. Changing networks — home Wi-Fi versus cellular — changes the public address because each network has its own. That does not mean the old address was “hacked.” It means you switched paths. Approximate city or country, when a tool shows one, is a guess from the network, not a GPS lock on your sofa.

Hosting a game server, a camera, or inbound connections is harder behind CGNAT because many customers share one public IPv4 address. A speed test still works. Port forwarding often does not. IPv6, when your ISP offers it, can restore a unique address for those jobs. Neither version by itself makes download, upload or ping better. Routing and congestion still decide the numbers on the speed test.

If the line feels slow, the address is rarely the first place to look. Measure the path, then isolate Wi-Fi versus the last mile. Start with why internet is slow and how to debug the connection. Use the IP page when you need to see which public address this network is using right now, including both families when your connection is dual-stack.

Common questions