IPv4 Lookup
IPv4 Lookup: Find Location and Network Details
Enter an IPv4 address (the dotted-decimal format, like 203.0.113.42) to see its location, ISP, ASN, and organization.
How to check or find an IPv4 address
Looking to check an IPv4 address instead of just reading about the format? Use the IPv4 lookup tool above: enter any IPv4 address and this page returns its approximate location, ISP, ASN, and connection type immediately, the same way it just did for your own connection. It works as an IPv4 finder, IPv4 tracker, and IPv4 checker all in one, there's no separate mode to switch, just type the address and search.
What is IPv4?
IPv4 is the original addressing format the internet was built on: four numbers from 0 to 255 separated by dots, like 203.0.113.42. It's still what most home routers, ISPs, and websites use by default, even though its roughly 4.3 billion possible addresses were fully allocated years ago. ISPs now stretch that limited supply with techniques like carrier-grade NAT, which is part of why several devices on the same network often share one public IPv4 address.
Public vs. private IPv4 addresses
Not every IPv4 address is reachable from the internet. Three ranges, 10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255, and 192.168.0.0 to 192.168.255.255, are reserved for private networks: routers hand these out to devices on a local subnet, and they're never routed on the public internet. This tool works on public IPv4 addresses; searching a private one won't return location data, since it isn't globally unique the way a public address is.
IPv4 vs. IPv6, in short
IPv6 exists specifically to solve IPv4's address shortage, with a space large enough that exhaustion isn't a realistic concern. Most networks run both side by side today, which is why the address detected for you on the homepage could be either format depending on your ISP and device. If you need to look up an IPv6 address specifically, use IPv6 Lookup instead.
Frequently asked questions
What does an IPv4 address look like?
Four numbers from 0-255 separated by dots, like 203.0.113.42. Each number is one byte, which is why IPv4 tops out at roughly 4.3 billion possible addresses.
Why is IPv4 running out of addresses?
IPv4 was designed in the 1980s for a much smaller internet, and 4.3 billion addresses have long since been allocated. Carrier-grade NAT, private ranges, and IPv6 are all workarounds for the same underlying shortage.
Can I look up a private IPv4 address here?
No, private IPv4 addresses (like 192.168.x.x) aren't globally routable, so there's no location data to return. This tool only works for public IPv4 addresses reachable from the internet.
Can I look up an IPv6 address here?
Not on this page, it's restricted to IPv4 so the content stays focused. Use IP Lookup for either format, or IPv6 Lookup for IPv6 addresses specifically.