Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Say I have the private network address and I want to split it into 2 subnets.

There are 12 bits used for the network number leaving 20 bit for the host number. I use 1 of these host bits as a subnet number giving me 2 subnets and leaving me with 19 bits for the host number.

This will mean I will have 2^19 - 2 = 524286 IP addresses per subnet?

And the second subnet address will be The broadcast address of the second subnet will be

Have I got that correct?

share|improve this question
up vote 3 down vote accepted

Yes, these numbers are correct. There are several IP subnet calculators on the internet that will help confirm these types of calculation, as well as phone apps.

Note that it is only in niche scenarios that such a large network would be useful, let alone a good idea.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.