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
/2711111111111111111111111111100000network bitshost bits

How many usable host addresses H are there in an IPv4 subnet with prefix /27?

/27
H =
2.Easy
/2411111111111111111111111100000000network bitshost bits

How many usable host addresses H are there in an IPv4 subnet with prefix /24?

/24
H =
3.Medium
/16 → /2011111111111111111111000000000000network bitshost bits

The network 172.20.0.0/16 is divided into equal subnets with prefix /20. How many subnets N are there?

172.20.0.0/16/20
N =
4.Medium
/?11111111111111111111110000000000network bitshost bits

A department needs 959 host addresses in a single subnet. What is the longest prefix length p (smallest subnet) that is big enough?

959 hosts
p =
5.Hard
last octet = 146112806403211608041201networkhost

A host has the address 10.20.251.146/25. What is the fourth octet x of its network address?

10.20.251.146/25
x =
6.Hard

The network 192.168.0.0/24 is split with VLSM for these LANs: A: 18 hosts, B: 5 hosts, C: 36 hosts, D: 9 hosts, E: 13 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: 18B: 5C: 36D: 9E: 13
x =

Answer key

  1. 1. H = 30
  2. 2. H = 254
  3. 3. N = 16
  4. 4. p = 22
  5. 5. x = 128
  6. 6. x = 128

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