Supernet Calculator Supernet Calculator

Network Class

First Octet Range

IP Address

. . .

Supernet Mask

Mask Bits

Wildcard Mask

Maximum Supernets

Maximum Addresses

Supernet Route

Supernet Address Range

Historical Supernet Network Calculator

The IP Supernet Calculator enables Supernet network calculations using network class, IP address, subnet mask, mask bits, maximum required IP addresses and maximum required supernets.

Results of the supernet calculation provide the wildcard mask, for use with ACL (Access Control Lists), supernet route (supernet network address) and the supernet address range for the resulting supernet network.

For classless supernetting, please use the CIDR Calculator. For classful subnetting, please use the IP Subnet Calculator. For simple ACL (Access Control List) wildcard mask calculations, please use the ACL Wildcard Mask Calculator.

What is This Network Calculator All About?

Notes: 2023, Clive Porter

This calculator has been made available for historical reasons. Please do not use it for production network calculations!

I will try to explain it in more detail here when I have time, but for the moment consider it a bit of networking history and try not to go crazy understanding what it does and why it exists!

Briefly, I first came across this type of calculator in the mid to late 90s. It was a Windows installable program but I don't remember the publisher. It was a puzzling beast and I needed to understand what it was doing.

As far as I am aware and certainly in my experience, this form of supernetting was never implemented. I can understand why, but it fascinates me that anybody should take the time to devise such a scheme!

The text I added at the bottom under 'Notes' was a result of what I managed to understand while developing this calculator. If you have any further information as to the why and how of this specimen, I\'d be interested to hear it.

Have fun with it!

Notes about the Supernet Calculator:
  1. The supernet calculator implements a classful / classed IP addressing scheme where the following rules are adhered to:

    • Class A addresses have their first octet in the range 1 to 126 (binary address begins with 0).

    • Class B addresses have their first octet in the range 128 to 191 (binary address begins with 10).

    • Class C addresses have their first octet in the range 192 to 223 (binary address begins with 110).

  2. The supernet calculator allows networks to be supernetted using the bits available between the network class bits and the subnet bits. i.e. class A networks use the first bit to specify the class and the first eight bits to specify the network prefix. The bits available, therefore, for supernetting are bits 2 to bits 8. Following the same rule, class B networks can be supernetted using bits 3 to 16 and class C with bits 4 to 24.

For classless supernetting, you can use the CIDR calculator.