Netmask Subnet Calculator

Use our Netmask subnet calculator below to show information about the subnet you enter.

In addition to a CIDR notation, the prefix can also be specified as a network mask which has the same quad-dotted decimal representation an IP address does. For example is the network mask for

When using the CIDR notation, the prefix size represents the number of most significant bits. For example, the binary representation for a prefix size of 24 is 11111111.11111111.11111111.00000000, or in quad-dotted decimal notation.

The network mask is also called subnet mask if it designates a subnet within a larger hierarchy network.

Get started below with your own netmask calculation. Enter in a IP address and then select the network mask. Our netmask subnet calculator will handle the rest and show you all relevant information about the subnet.

IP address Netmask