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
255.255.128.011111111111111111000000000000000network bitshost bits

A subnet has the mask 255.255.128.0. What is its prefix length p?

255.255.128.0
p =
2.Easy
third octet of /22112816413211618140201oneszeros

Write the subnet mask of a /22 network in dotted-decimal notation. What is the value x of its third octet?

/22
x =
3.Medium
/?11111111111111111111100000000000network bitshost bits

A department needs 1375 host addresses in a single subnet. What is the longest prefix length p (smallest subnet) that is big enough?

1375 hosts
p =
4.Medium
/24 → /2611111111111111111111111111000000network bitshost bits

The network 192.168.10.0/24 must be divided into at least 3 equal subnets. If you borrow as few bits as possible, how many usable hosts H does each subnet have?

192.168.10.0/243 subnets
H =
5.Hard
last octet = 108012816413201618140201networkhost

A host has the address 10.20.126.108/26. What is the fourth octet x of the last usable host address in its subnet?

10.20.126.108/26
x =
6.Hard
last octet = 199112816403201608141211networkhost

A host has the address 10.20.198.199/30. What is the fourth octet x of the last usable host address in its subnet?

10.20.198.199/30
x =

Answer key

  1. 1. p = 17
  2. 2. x = 252
  3. 3. p = 21
  4. 4. H = 62
  5. 5. x = 126
  6. 6. x = 198

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