Subnet Address
Which subnet does host 10.67.17.74 255.255.240.0 belong to?
Example 2:
Which subnet does host 10.115.63.136 255.255.240.0 belong to?
Example 3:
Which subnet does host 10.197.42.228/20 belong to?
Example 4:
What is the subnet address if the IP address is 144.16.34.124 and the subnet mask is 255.255.240.0?
Example 5:
What is the subnetwork number of a host with an IP address of 172.16.67.0/21?
Example 6:
Which subnet does host 172.16.168.107 255.255.252.0 belong to?
Example 7:
Which subnet does host 172.16.210.0/22 belong to?
Example 8:
Which subnet does host 172.19.73.42/22 belong to?
Example 9:
Which subnet does host 172.20.62.253/24 belong to?
Example 10:
Which subnet does host 172.21.252.26/28 belong to?
Example 11:
Which subnet does host 172.21.132.197/27 belong to?
Example 12:
Which subnet does host 172.23.210.182/21 belong to?
Example 13:
Which subnet does host 172.21.112.211/23 belong to?
Example 14:
Which subnet does host 172.23.88.104 255.255.255.0 belong to?
Example 15:
What is the subnetwork number of a host with an IP address of 172.23.182.124/20?
Example 16:
Which subnet does host 172.24.24.199 255.255.255.128 belong to?
Example 17:
Which subnet does host 172.24.115.11 255.255.255.224 belong to?
Example 18:
Which subnet does host 172.24.177.221 255.255.240.0 belong to?
Example 19:
Which subnet does host 172.27.177.101 255.255.255.224 belong to?
Example 20:
Which subnet does host 192.168.6.198 255.255.255.224 belong to?
Example 21:
Which subnet does host 192.168.19.245 255.255.255.240 belong to?
Example 22:
Which subnet does host 192.168.49.1 255.255.255.192 belong to?
Example 23:
Which subnet does host 192.168.52.158 255.255.255.192 belong to?
Example 24:
Which subnet does host 192.168.75.106 255.255.255.252 belong to?
Example 25:
Which subnet does host 192.168.112.146 255.255.255.128 belong to?
Example 26:
Which subnet does host 192.168.145.228/27 belong to?
Example 27:
Which subnet does host 192.168.159.218 255.255.255.252 belong to?
Example 28:
Which subnet does host 192.168.78.2/27 belong to?
Example 29:
Which subnet does host 192.168.105.2 255.255.255.192 belong to?
Example 30:
Which subnet does host 192.168.180.156/27 belong to?
Example 31:
What is the subnet address of the IP address 192.168.200.33 255.255.255.248?
Class A
Example: 1
Which subnet does host 10.67.17.74 255.255.240.0 belong to?Solution:
Class A addresses use a default mask of 255.0.0.0
Given subnet mask = 255.255.240.0 (/22)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the third octet.
Count by 16 until reaching 17.
Subnets are 0, 16, 32 etc.
Address 17 falls in the 16 subnet.
Subnet = 10. 67. 16. 0
Example: 2
Which subnet does host 10.115.63.136 255.255.240.0 belong to?Solution:
Class A addresses use a default mask of 255.0.0.0
Given subnet mask = 255.255.240.0 (/22)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the third octet.
Count by 16 until reaching 63.
Subnets are 0, 16, 32, 48, 64 etc.
Address 63 falls in the 48 subnet.
Subnet = 10. 115. 48. 0
Example: 3
Which subnet does host 10.197.42.228/20 belong to?Solution:
Class A addresses use a default mask of 255.0.0.0
Given subnet mask = 255.255.240.0 (/20)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the third octet.
Count by 16 until reaching 42.
Subnets are 0, 16, 32, 48 etc.
Address 42 falls in the 32 subnet.
Subnet = 10. 197. 32. 0
Class B
Example: 4
What is the subnet address if the IP address is 144.16.34.124 and the subnet mask is 255.255.240.0?Solution:
34 :: 00100010
240 :: 11110000
And :: 00100000=32
Subnet address will be 144. 16. 32 .0
Another way:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.240.0 (/20)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the third octet.
Count by 16 until reaching 34.
Subnets are 0, 16, 32, 48 etc.
Address 34 falls in the 32 subnet.
Subnet = 144. 16. 32. 0
Example: 5
What is the subnetwork number of a host with an IP address of 172.16.67.0/21?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.248.0 (/21)
Valid subnets = 256 - 248 = 8, which means we have a block
size of 8 in the third octet.
Count by 8 until reaching 66.
Subnets are 0, 8, 16, 24, 32, 40, 48, 56, 64, 72 etc.
Address 67 falls in the 64 subnet.
Subnet = 172. 16. 64. 0
Example: 6
Which subnet does host 172.16.168.107 255.255.252.0 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.252.0 (/22)
Valid subnets = 256 - 252 = 4, which means we have a block
size of 4 in the third octet.
Count by 4 until reaching 168.
Subnets are 0, 4, 8, ... ,164, 168, 172 etc.
Address 168 falls in the 168 subnet.
Subnet = 172. 16. 168. 0
Example: 7
Which subnet does host 172.16.210.0/22 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.252.0 (/22)
Valid subnets = 256 - 252 = 4, which means we have a block
size of 4 in the third octet.
Count by 4 until reaching 210.
Subnets are 0, 4, 8, ... , 208, 212 etc.
Address 210 falls in the 208 subnet.
Subnet = 172. 16. 208. 0
Example: 8
Which subnet does host 172.19.73.42/22 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.252.0 (/22)
Valid subnets = 256 - 252 = 4, which means we have a block
size of 4 in the third octet.
Count by 4 until reaching 73.
Subnets are 0, 4, 8, ... , 72, 76 etc.
Address 73 falls in the 72 subnet.
Subnet = 172. 19. 72. 0
Example: 9
Which subnet does host 172.20.62.253/24 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.0 (/24)
Valid subnets = 256 - 255 = 1, which means we have a block
size of 1 in the third octet.
Count by 1 until reaching 62.
Subnets are 0, 1, 2, ... , 61, 62 etc.
Address 62 falls in the 62 subnet.
Subnet = 172. 20. 62. 0
Example: 10
Which subnet does host 172.21.252.26/28 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.240 (/28)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the forth octet.
Count by 16 until reaching 26.
Subnets are 0, 16, 32, 48 etc.
Address 26 falls in the 16 subnet.
Subnet = 172. 21. 252. 16
Example: 11
Which subnet does host 172.21.132.197/27 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Count by 32 until reaching 197.
Subnets are 0, 32, 64, ... , 160, 192, 224 etc.
Address 197 falls in the 192 subnet.
Subnet = 172. 21. 132. 192
Example: 12
Which subnet does host 172.23.210.182/21 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.248.0 (/21)
Valid subnets = 256 - 248 = 8, which means we have a block
size of 8 in the third octet.
Count by 8 until reaching 210.
Subnets are 0, 8, 16, ... , 208, 216 etc.
Address 210 falls in the 208 subnet.
Subnet = 172. 23. 208. 0
Example: 13
Which subnet does host 172.21.112.211/23 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.254.0 (/23)
Valid subnets = 256 - 254 = 2, which means we have a block
size of 2 in the third octet.
Count by 2 until reaching 112.
Subnets are 0, 2, 4, 6, ... , 110, 112 etc.
Address 112 falls in the 112 subnet.
Subnet = 172. 21. 112. 0
Example: 14
Which subnet does host 172.23.88.104 255.255.255.0 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.0 (/24)
Valid subnets = 256 - 255 = 1, which means we have a block
size of 1 in the third octet.
Count by 1 until reaching 88.
Subnets are 0, 1, 2, ... , 87 , 88 etc.
Address 88 falls in the 88 subnet.
Subnet = 172. 23. 88. 0
Example: 15
What is the subnetwork number of a host with an IP address of 172.23.182.124/20?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.240.0 (/20)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the third octet.
Count by 16 until reaching 182.
Subnets are 0, 16, 32, ... , 160, 176, 192 etc.
Address 182 falls in the 176 subnet.
Subnet = 172. 23. 176. 0
Example: 16
Which subnet does host 172.24.24.199 255.255.255.128 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.128 (/25)
Valid subnets = 256 - 128 = 128, which means we have a block
size of 128 in the forth octet.
Count by 128 until reaching 199.
Subnets are 0, 128, 256.
Address 199 falls in the 128 subnet.
Subnet = 172. 24. 24. 128
Example: 17
Which subnet does host 172.24.115.11 255.255.255.224 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Subnets are 0, 32, 64 etc.
Address 11 falls in the 0 subnet.
Subnet = 172. 24. 115. 0
Example: 18
Which subnet does host 172.24.177.221 255.255.240.0 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.240.0 (/20)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the third octet.
Count by 16 until reaching 177.
Subnets are 0, 16, ... , 160, 176, 192 etc.
Address 177 falls in the 176 subnet.
Subnet = 172. 24. 176. 0
Example: 19
Which subnet does host 172.27.177.101 255.255.255.224 belong to?Solution:
Class B addresses use a default mask of 255.255.0.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Count by 32 until reaching 101.
Subnets are 0, 32, ... , 64, 96, 128 etc.
Address 101 falls in the 96 subnet.
Subnet = 172. 27. 177. 96
Class C
Example: 20
Which subnet does host 192.168.6.198 255.255.255.224 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Count by 32 until reaching 198.
Subnets are 0, 32, ... , 160, 192, 224 etc.
Address 198 falls in the 192 subnet.
Subnet = 192. 168. 6. 192
Example: 21
Which subnet does host 192.168.19.245 255.255.255.240 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.240 (/28)
Valid subnets = 256 - 240 = 16, which means we have a block
size of 16 in the forth octet.
Count by 16 until reaching 245.
Subnets are 0, 16, ... , 224, 240, 256.
Address 245 falls in the 240 subnet.
Subnet = 192. 168. 19. 240
Example: 22
Which subnet does host 192.168.49.1 255.255.255.192 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.192 (/26)
Valid subnets = 256 - 192 = 64, which means we have a block
size of 64 in the forth octet.
Subnets are 0, 64, 128, 256
Address 1 falls in the 0 subnet.
Subnet = 192. 168. 49. 0
Example: 23
Which subnet does host 192.168.52.158 255.255.255.192 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.192 (/26)
Valid subnets = 256 - 192 = 64, which means we have a block
size of 64 in the forth octet.
Count by 64 until reaching 158.
Subnets are 0, 64, 128, 192 etc.
Address 158 falls in the 128 subnet.
Subnet = 192. 168. 52. 128
Example: 24
Which subnet does host 192.168.75.106 255.255.255.252 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.252 (/30)
Valid subnets = 256 - 252 = 4, which means we have a block
size of 4 in the forth octet.
Count by 4 until reaching 106.
Subnets are 0, 4, 8, ... , 100, 104, 108 etc.
Address 106 falls in the 104 subnet.
Subnet = 192. 168. 75. 104
Example: 25
Which subnet does host 192.168.112.146 255.255.255.128 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.128 (/25)
Valid subnets = 256 - 128 = 128, which means we have a block
size of 128 in the forth octet.
Count by 128 until reaching 146.
Subnets are 0, 128, 256.
Address 146 falls in the 128 subnet.
Subnet = 192. 168. 112. 128
Example: 26
Which subnet does host 192.168.145.228/27 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Count by 32 until reaching 228.
Subnets are 0, 32, 64, ... , 224, 256.
Address 228 falls in the 224 subnet.
Subnet = 192. 168. 145. 224
Example: 27
Which subnet does host 192.168.159.218 255.255.255.252 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.252 (/30)
Valid subnets = 256 - 252 = 4, which means we have a block
size of 4 in the forth octet.
Count by 4 until reaching 218.
Subnets are 0, 4, 8, ... , 216, 220 etc.
Address 218 falls in the 216 subnet.
Subnet = 192. 168. 159. 216
Example: 28
Which subnet does host 192.168.78.2/27 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Subnets are 0, 32, 64 etc.
Address 2 falls in the 0 subnet.
Subnet = 192. 168. 78. 0
Example: 29
Which subnet does host 192.168.105.2 255.255.255.192 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.192 (/26)
Valid subnets = 256 - 192 = 64, which means we have a block
size of 64 in the forth octet.
Subnets are 0, 64 etc.
Address 2 falls in the 0 subnet.
Subnet = 192. 168. 105. 0
Example: 30
Which subnet does host 192.168.180.156/27 belong to?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.224 (/27)
Valid subnets = 256 - 224 = 32, which means we have a block
size of 32 in the forth octet.
Count by 32 until reaching 156.
Subnets are 0, 32, 64, ... , 96, 128, 160 etc.
Address 156 falls in the 128 subnet.
Subnet = 192. 168. 180. 128
Example: 31
What is the subnet address of the IP address 192.168.200.33 255.255.255.248?Solution:
Class C addresses use a default mask of 255.255.255.0
Given subnet mask = 255.255.255.248 (/29)
Valid subnets = 256 - 248 = 8, which means we have a block
size of 8 in the forth octet.
Count by 8 until reaching 33.
Subnets are 0, 8, 16, 24, 32, 40 etc.
Address 33 falls in the 32 subnet.
Subnet = 192. 168. 200. 32
