Netmask Inverse /CIDR Usable Size
255.255.255.255 0.0.0.0 /32 1 1 Host
255.255.255.254 0.0.0.1 /31 0 2 Hosts
255.255.255.252 0.0.0.3 /30 2 4 Hosts
255.255.255.248 0.0.0.7 /29 6 8 Hosts
255.255.255.240 0.0.0.15 /28 14 16 Hosts
255.255.255.224 0.0.0.31 /27 30 32 Hosts
255.255.255.192 0.0.0.63 /26 62 64 Hosts
255.255.255.128 0.0.0.127 /25 126 128 Hosts
255.255.255.0 0.0.0.255 /24 254 1 Class 'C'
255.255.254.0 0.0.1.255 /23 510 2 Class 'C's
255.255.252.0 0.0.3.255 /22 1,022 4 Class 'C's
255.255.248.0 0.0.7.255 /21 2,046 8 Class 'C's
255.255.240.0 0.0.15.255 /20 4,094 16 Class 'C's
255.255.224.0 0.0.31.255 /19 8,190 32 Class 'C's
255.255.192.0 0.0.63.255 /18 16,382 64 Class 'C's
255.255.128.0 0.0.127.255 /17 32,766 128 Class 'C's
255.255.0.0 0.0.255.255 /16 65,534 1 Class 'B'
255.254.0.0 0.1.255.255 /15 131,070 2 Class 'B's
255.252.0.0 0.3.255.255 /14 262,142 4 Class 'B's
255.248.0.0 0.7.255.255 /13 524,286 8 Class 'B's
255.240.0.0 0.15.255.255 /12 1,048,574 16 Class 'B's
255.224.0.0 0.31.255.255 /11 2,097,150 32 Class 'B's
255.192.0.0 0.63.255.255 /10 4,194,302 64 Class 'B's
255.128.0.0 0.127.255.255 /9 8,388,606 128 Class 'B's
255.0.0.0 0.255.255.255 /8 16,777,214 1 Class 'A'
254.0.0.0 1.255.255.255 /7 33,554,430 2 Class 'A's
252.0.0.0 3.255.255.255 /6 67,108,862 4 Class 'A's
248.0.0.0 7.255.255.255 /5 134,217,726 8 Class 'A's
240.0.0.0 15.255.255.255 /4 268,435,454 16 Class 'A's
224.0.0.0 31.255.255.255 /3 536,870,910 32 Class 'A's
192.0.0.0 63.255.255.255 /2 1,073,741,822 64 Class 'A's
128.0.0.0 127.255.255.255 /1 2,147,483,646 128 Class 'A's
0.0.0.0 255.255.255.255 /0 4,294,967,294 The Internet (ALL Hosts)
