What is a subnet?

A subnet is a smaller segment carved out of a larger network. Splitting a network into subnets keeps traffic organized and helps devices find each other faster within that slice.

Routers use subnet masks or prefixes to tell where one subnet ends and another begins. Devices within the same subnet can communicate directly, while traffic crossing subnets typically goes through a router or gateway.

Subnets also make managing IP addresses easier. You can dedicate ranges for workstations, guest Wi-Fi, or printers, reducing congestion and keeping sensitive systems isolated.

Because IPLookup.help reports the public IP your subnet shares, you can confirm whether your subnet's router is the address the world sees, even if each device has a private IP.