IPv4 subnetting worksheet with answers

Free printable IPv4 subnetting worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
/2111111111111111111111100000000000network bitshost bits

How many usable host addresses H are there in an IPv4 subnet with prefix /21?

/21
H =
2.Easy
/2311111111111111111111111000000000network bitshost bits

How many usable host addresses H are there in an IPv4 subnet with prefix /23?

/23
H =
3.Medium
/?11111111111111111111100000000000network bitshost bits

A department needs 1796 host addresses in a single subnet. What is the longest prefix length p (smallest subnet) that is big enough?

1796 hosts
p =
4.Medium
/24 → /2811111111111111111111111111110000network bitshost bits

The network 10.63.236.0/24 is divided into equal subnets with prefix /28. How many subnets N are there?

10.63.236.0/24/28
N =
5.Hard

The network 192.168.8.0/24 is split with VLSM for these LANs: A: 7 hosts, B: 20 hosts, C: 34 hosts, D: 41 hosts. Subnets are allocated from .0 upwards, the LAN with the most hosts first, each with the smallest subnet that fits. What is the fourth octet x of the network address of LAN B?

A: 7B: 20C: 34D: 41
x =
6.Hard
third octet 191 … 197112806413211618141211commonvaries

A router has routes to these networks: 10.171.191.0/24, 10.171.192.0/24, 10.171.193.0/24, 10.171.194.0/24, 10.171.195.0/24, 10.171.196.0/24, 10.171.197.0/24. What is the longest prefix length p of a single summary route that covers all of them?

10.171.191.0/24 … 10.171.197.0/24
p =

Answer key

  1. 1. H = 2046
  2. 2. H = 510
  3. 3. p = 21
  4. 4. N = 16
  5. 5. x = 128
  6. 6. p = 17

Full step-by-step solutions: practise this topic on examproblems.com.