How to calculate a subnet mask from hosts and subnets | TechTarget
Subnet Calculator Download: Find out the network and broadcast address, subnet and wildcard masks, total available hosts, and other details based on the IP address
IP Calculater Web Tools [cmdref.net - Cheat Sheet and Example]
IP Subnet Calculator
IP Calculator / IP Subnetting
Creating a Subnet
IPv4 Subnet Calculator Console Version - TerrorFlatRider