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.

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Name: ____________________   Date: ____________

1.Easy
/2911111111111111111111111111111000network bitshost bits

How many usable host addresses H are there in an IPv4 subnet with prefix /29?

/29
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
/24 → /2611111111111111111111111111000000network bitshost bits

The network 192.168.253.0/24 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?

192.168.253.0/24/26subnet 4 (subnet 1 starts at .0)
x =
4.Medium
/?11111111111111111111100000000000network bitshost bits

A department needs 1564 host addresses in a single subnet. What is the longest prefix length p (smallest subnet) that is big enough?

1564 hosts
p =
5.Hard
third octet = 57012806413211618040211networkhost

A host has the address 172.20.57.151/19. What is the third octet x of its subnet's broadcast address?

172.20.57.151/19
x =
6.Hard
third octet 188 … 193112806413211618140201commonvaries

A router has routes to these networks: 10.32.188.0/24, 10.32.189.0/24, 10.32.190.0/24, 10.32.191.0/24, 10.32.192.0/24, 10.32.193.0/24. What is the longest prefix length p of a single summary route that covers all of them?

10.32.188.0/24 … 10.32.193.0/24
p =

Answer key

  1. 1. H = 6
  2. 2. H = 510
  3. 3. x = 255
  4. 4. p = 21
  5. 5. x = 63
  6. 6. p = 17

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