Here are two wonderful tools to help you with your subnetting
FREE IP Subnet Calculator
This is the fastest and most versatile IP subnet calculator available on the web today. It took months to develop and thousands of dollars but you can have it with our complements. Please do not mistake it for other inferior IP calculators you can download, this one is the most robust one you will ever use.
Download it for free below or launch it now by clicking here. You must have java on your machine which you can get from here.
Free Subnetting Question Generator
If you don’t want to go to the trouble of working out your own subnetting questions then please feel free to use this tool. It will ask you question after question about subnetting and network design. Imagine how great you will feel when you are answering every question in a few seconds!
To get the full Subnetting Secrets course on howtonetwork.com please hit the ‘Get Access Now’ button.