How Public IP and Domain Lookups Work
Understand public IP addresses, hostname resolution, approximate location data, and the limits of IP lookup results.
What an IP lookup can tell you
A public IP address identifies the internet connection used for a request. An IP lookup can associate that address with an internet provider, autonomous system, approximate region, and timezone. These values come from network registration and geolocation datasets; they do not reveal a precise home address and can be wrong when a provider routes traffic through another city.
A domain-to-IP lookup answers a different question. DNS resolves a hostname such as example.com to one or more addresses used to reach its service. Large sites often return several addresses, use content delivery networks, or change answers by location.
How to run a useful check
- Use What Is My IP to inspect the public address seen from the connection.
- Use Domain to IP when diagnosing a hostname rather than a person or device.
- Compare the returned address with DNS records and hosting information when investigating routing.
How to interpret the result
A VPN, corporate gateway, mobile carrier, or proxy can make many users appear behind one address. IPv4 addresses may also be shared through carrier-grade NAT. IPv6 generally provides a much larger address space, but an IPv6 address still should not be treated as proof of identity.
Common mistakes
Do not use geolocation as a precise location claim, assume a domain has only one server, or treat an ISP name as the owner of a website. For abuse or legal questions, rely on authoritative provider records and an appropriate process.