Netmask v. Address Prefix Length

Netmask    Address Prefix Length    Hosts / Class C's / Class B's / Class A's
255.255.255.255    /32    1
255.255.255.254    /31    2
255.255.255.252    /30    4
255.255.255.248    /29    8
255.255.255.240    /28    16
255.255.255.224    /27    32
255.255.255.192    /26    64
255.255.255.128    /25    128
255.255.255.0    /24 (Class C)    256 / 1
255.255.254.0    /23    512 / 2
255.255.252.0    /22    1,024 / 4
255.255.248.0    /21    2,048 / 8
255.255.240.0    /20    4,096 / 16
255.255.224.0    /19    8,192 / 32
255.255.192.0    /18    16,384 / 64
255.255.128.0    /17    32,768 / 128
255.255.0.0    /16 (Class B)    65,536 / 256 / 1
255.254.0.0    /15    131,072 / 512 / 2
255.252.0.0    /14    262,144 / 1024 / 4
255.248.0.0    /13    524,288 / 2048 / 8
255.240.0.0    /12    1,048,576 / 4096 / 16
255.224.0.0    /11    2,097,152 / 8129 / 32
255.192.0.0    /10    4,194,304 / 16,384 / 64
255.128.0.0    /9    8,388,608 / 32,768 / 128
255.0.0.0    /8 (Class A)    16,777,216 / 65,536 / 256 / 1
254.0.0.0    /7    33,554,432 / 131,072 / 512 / 2
252.0.0.0    /6    67,108,864 / 262,144 / 1,024 / 4
248.0.0.0    /5    134,217,728 / 524,288 / 2,048 / 8
240.0.0.0    /4    268,435,456 / 1,048,576 / 4,096 / 16
224.0.0.0    /3    536,870,912 / 2,097,152 / 8,192 / 32
192.0.0.0    /2    1,073,741,824 / 4,194,304 / 16,384 / 64
128.0.0.0    /1    2,147,483,648 / 8,388,608 / 32,768 / 128
0.0.0.0    /0 (The Internet)    4,294,967,296 / 16,777,216 / 65,536 / 256
























































































































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