Avatar of jskfan
Flag for Cyprus asked on

Calculating the Subnets.

Calculating the Subnets.

I am using the online Subnet Calculator.  Some Data displayed on the calculator and indicated by the Red arrows on the screenshot below  need some explanation:

how did they come with subnet bits: 12
Maximum subnets 4096
host per subnets :14
subnet ID :
Broadcast address :

Thank you


Avatar of undefined
Last Comment

8/22/2022 - Mon

Log in or sign up to see answer
Become an EE member today7-DAY FREE TRIAL
Members can start a 7-Day Free trial then enjoy unlimited access to the platform
Sign up - Free for 7 days
Learn why we charge membership fees
We get it - no one likes a content blocker. Take one extra minute and find out why we block content.
Not exactly the question you had in mind?
Sign up for an EE membership and get your own personalized solution. With an EE membership, you can ask unlimited troubleshooting, research, or opinion questions.
ask a question
Don Johnston

how did they come with subnet bits: 12

You start with an address that has a 16-bit mask.   You extend the mask to accommodate the number of subnets/hosts and you end up with a 28-bit mask.  


Actual mask minus the original (or starting) mask will give the size of the subnet field.  Which in this case is 12.

You chose class B network mask, so your results of a /28 is 12 bits in from the /16. Now if you go back and choose class C network, you will only be 4 bits from the /24.


can you clarify this :
Your first usable subnet will be
Experts Exchange has (a) saved my job multiple times, (b) saved me hours, days, and even weeks of work, and often (c) makes me look like a superhero! This place is MAGIC!
Walt Forbes

jsk -

Sorry - should say

Your first usable subnet will be
First address in the subnet is
Last address in the subnet is
First address in a subnet is always the network address and unusable (subnet ID)
Last address in a subnet is always the broadcast address and unusable (Broadcast Address)

Does that clarify?

Thank you for clear explanation