Subnetting Calculator.NET was designed with network administrators in mind. Just enter in the the IP address or Network address and the select the Subnetmask. You will then know what network the address is on, all other networks available, if the Address is a Network ID, Broadcast ID or good for a host, the binary format of the Network ID, Subnet mask and IP Address. Inludes Auto-Update, so you can always get the latest updates (Free).

Features:
IP & Network ID Converted to Binary
Listing of all possible Network & Broadcast ID's
IP Class, Type, Range, Good for Host, Total Hosts per Network, Total Networks
Automatic Updates
Host Look Up
Ping Remote Host
Trace Route from Local Machine to Remote Host
Display Routing Table of Current Machine
Convert numbers upto and including 999,999,999,999,999,999 to Binary, Octal, And Hex