CIDR Calculator icon

App Specs
File size:
615.69 KB
January 30, 2012
January 9, 2013

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CIDR Calculator was designed out of a desire to streamline CIDR calculations by creating a simple, easy to use tool for performing CIDR network block math and network masks with complete confidence.

A cornerstone of worldwide IPv4 network communications is Classless Inter-Domain Routing, also known as CIDR. CIDR blocks help routers move packets based on a shorthand method of telling another system what IP ranges the devices can route. Now, if you're looking at this tool, you most likely know more about CIDR than I can possibly cover here, so I'll focus on the unique features of this Application:

CIDR Calculator is a simple to use tool that allows rapid deconstruction and understanding of any valid CIDR block notation.

For example. You've received a block of IP's from your ISP. Maybe they are add-ons to your existing network. Perhaps you are deploying a completely new network. When you look at the provisioning worksheet and see the notation you will want to know what IPs are part of that range. Instead of trying to do perform the 32-bit math in your head, or on a calculator, why not just use this handy tool? If you with a simple push of a button you'd have known:

  • The true starting IP address of the block:

  • The top, or end of the IP block:

  • The decimal equivalent of both the starting and ending IP ranges. Useful in only a few situations, but when you need it, you really need it. (In this case they are 301713408 and 301713535 respectively).


Don't spend your time calculating the offset with your scientific calculator, just use CIDR Calculator.

  • What's New
  • Updated help documentation. Original version was rather embarrassing.
  • Clarified some topics in help book.

  • CIDR Calculator (com.daviddemartini.osx.cidrcalc) is a Mac software application that has been discovered and submitted by users of

    Operating System: Mac

    Default Install Path: /Applications/CIDR

    Minimum OS version: 10.6

    Copyright: Copyright (c) 2012 David DeMartini. All rights reserved.