Network Calculator
Your browser does not support JavaScript (if you are using Netscape 3 or higher or Microsoft Internet Explorer 4 or higher you may have JavaScript turned off in your network preferences), so you cannot use the Network Calculators. If you use a JavaScript-capable browser, such as the newer versions of Microsoft Internet Explorer or Netscape Navigator, you'll be able to use the calculators.
Netscape Navigator 4.0.x Users: There is a known bug in Netscape Navigator 4.0.x which will cause you to see this message if you have the local cache turned off.
For help with any of the calculators, click here. If you think the calculator is wrong because it shows the first and last ('all zeroes' and 'all ones') subnets as being available, click here for an explanation.