The subnet calculator above is a handy tool for quickly determining the network range and the subnet mask of your network based on a CIDR notation. This is also helpful for finding the broadcast ip address of a network or the number of usable ip addresses within a subnet. There is even a convenient binary output to help you understand the relationship between the ip address and subnet from 8 bit binary notation.
Most network engineers who work with ip addresses frequently can figure most of this out in their head. However for the majority of folks building home networks, this convenient subnet calculator really helps quickly and accurately calculate your subnetworks.
This calculator is only for IPv4 addresses and will not support the newest IPv6 addresses. If you don't know what that means that's okay as almost all networks today are IPv4. One indication is if your network is IPv4 is to see if you you have 4 Octets as your ip address.
An IPv4 address would look like this:
192.168.10.5 - where you have four numbers (also known as Octets) separated by a DOT. The subnet mask would look similar
255.255.255.0 - Again you have four number separated by a dot. The number 255 indicates that this Octets is masked (is part of the network and not to be used for addressing computers on your network.
This isn't anything fancy just a quick and dirty way to get IPv4 information quickly.
We hope it's useful!