IP subnet calculator

Enter an IPv4 address with a CIDR prefix, e.g. 192.168.1.10/24.

Network address
Broadcast address
Subnet mask
Wildcard mask
First usable host
Last usable host
Usable hosts
Total addresses

What is IP subnet calculator?

A CIDR block like 192.168.1.0/24 describes a range of IP addresses and how many of them belong to the same network — the "/24" is the subnet mask expressed as a bit count, and it determines the network address, broadcast address, and how many usable host addresses exist inside.

How to use it

Enter an address with its CIDR prefix. The tool works out the network and broadcast addresses, the subnet mask in dotted form, and the first/last usable host addresses.

Example

192.168.1.10/24 -> network 192.168.1.0, broadcast 192.168.1.255, usable hosts 192.168.1.1 - 192.168.1.254 (254 addresses)