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
fourth octet of /27112816413201608040201oneszeros

Write the subnet mask of a /27 network in dotted-decimal notation. What is the value x of its fourth octet?

/27
x =
2.Easy
/2311111111111111111111111000000000network bitshost bits

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

/23
H =
3.Medium
/24 → /3011111111111111111111111111111100network bitshost bits

The network 10.231.240.0/24 is divided into equal subnets with prefix /30. How many subnets N are there?

10.231.240.0/24/30
N =
4.Medium
/?11111111111111111111100000000000network bitshost bits

A department needs 1549 host addresses in a single subnet. What is the longest prefix length p (smallest subnet) that is big enough?

1549 hosts
p =
5.Hard
last octet = 36012806413201608140201networkhost

A host has the address 10.20.116.36/25. What is the fourth octet x of the last usable host address in its subnet?

10.20.116.36/25
x =
6.Hard
last octet = 171112806413201618041211networkhost

A host has the address 10.20.64.171/30. What is the last number (fourth octet) x of its subnet's broadcast address?

10.20.64.171/30
x =

Answer key

  1. 1. x = 224
  2. 2. H = 510
  3. 3. N = 64
  4. 4. p = 21
  5. 5. x = 126
  6. 6. x = 171

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