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
/2311111111111111111111111000000000network bitshost bits

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

/23
H =
2.Easy
/2111111111111111111111100000000000network bitshost bits

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

/21
H =
3.Medium
/24 → /2611111111111111111111111111000000network bitshost bits

The network 192.168.131.0/24 is divided into /26 subnets, numbered 1, 2, 3, … from the lowest address (subnet 1 starts at .0). What is the fourth octet x of the broadcast address of subnet 4?

192.168.131.0/24/26subnet 4 (subnet 1 starts at .0)
x =
4.Medium
255.255.255.12811111111111111111111111110000000network bitshost bits

A subnet uses the mask 255.255.255.128. How many usable host addresses H does it have?

255.255.255.128
H =
5.Hard
last octet = 160112806413201608040201networkhost

A host has the address 10.20.157.160/29. What is the last number (fourth octet) x of its subnet's broadcast address?

10.20.157.160/29
x =
6.Hard
third octet 247 … 252112816413211608141211commonvaries

A router has routes to these networks: 10.13.247.0/24, 10.13.248.0/24, 10.13.249.0/24, 10.13.250.0/24, 10.13.251.0/24, 10.13.252.0/24. What is the longest prefix length p of a single summary route that covers all of them?

10.13.247.0/24 … 10.13.252.0/24
p =

Answer key

  1. 1. H = 510
  2. 2. H = 2046
  3. 3. x = 255
  4. 4. H = 126
  5. 5. x = 167
  6. 6. p = 20

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