Routerpedia

Network tool

Subnet Calculator

Free IPv4 subnet calculator. Enter an IP and CIDR prefix to get network address, broadcast, usable hosts, and subnet mask.

Enter IP address and CIDR

Examples: 10.0.0.0/8 · 172.16.0.0/16 · 192.168.1.0/24

How to use the subnet calculator

Enter an IPv4 address and CIDR prefix (e.g. 192.168.1.0/24). The calculator shows the network range, subnet mask, and how many devices can fit on that subnet.

This is useful when configuring router LAN settings, VLANs, static IPs, or planning home network segments.