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
255.255.224.011111111111111111110000000000000network bitshost bits

A subnet has the mask 255.255.224.0. What is its prefix length p?

255.255.224.0
p =
2.Easy
third octet of /20112816413211608040201oneszeros

Write the subnet mask of a /20 network in dotted-decimal notation. What is the value x of its third octet?

/20
x =
3.Medium
255.255.248.011111111111111111111100000000000network bitshost bits

A subnet uses the mask 255.255.248.0. How many usable host addresses H does it have?

255.255.248.0
H =
4.Medium
/?11111111111111111111100000000000network bitshost bits

A department needs 1887 host addresses in a single subnet. What is the longest prefix length p (smallest subnet) that is big enough?

1887 hosts
p =
5.Hard
last octet = 151112806403211608141211networkhost

A host has the address 10.20.62.151/28. What is the fourth octet x of the last usable host address in its subnet?

10.20.62.151/28
x =
6.Hard
last octet = 110012816413201618141201networkhost

A host has the address 10.20.219.110/27. What is the last number (fourth octet) x of its subnet's broadcast address?

10.20.219.110/27
x =

Answer key

  1. 1. p = 19
  2. 2. x = 240
  3. 3. H = 2046
  4. 4. p = 21
  5. 5. x = 158
  6. 6. x = 127

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