This online IP subnet mask calculator can be used to get the subnet details using wildcard mask,
subnet mask or using prefix length. It provides the details about all the available IP address in the subnet, usable IPs, subnet id, network id, and their hex and binary values.
What is Subnetting/Network Masks?
A network mask helps to undertand the network portion of the IP address and host portion of the IP address. There are 3 default class for Network Masks.
Class A: 255.0.0.0
Class B: 255.255.0.0
Class C: 255.255.255.0
Subnetting is a method to borrow the host portion of the IP address in order to divide a larger network in to small network. For example if we have Class A subnet there are 16777216 IPs in the network.
Its not recommened to have a bigger network with these many hosts. Hence the subnet needs to be further divided into small networks. For this purpose we use subnetting.
Subnet mask is used to identify the Network portion and host portion of the IP address. Subnet mask is basically a continuous 1's and 0's. For example 255.0.0.0 in binary 11111111.00000000.00000000.00000000
In this first 8 bits are network portion and the remaining 24 bits are host portion. so in the corresponding IP address first 8 bits never get changed, only the host portion changes for each host in the network.