IPv4

 

Reserved ranges
10.0.0.0 – 10.255.255.255
127.0.0.0 – 127.255.255.255
172.16.0.0 – 172.16.255.255
192.168.0.0 – 192.168.255.255

 

Classful IP ranges
A 0.0.0.0 – 127.255.255.255
B 128.0.0.0 – 191.255.255.255
C 192.0.0.0 – 223.255.255.255
D 224.0.0.0 – 239.255.255.255
E 240.0.0.0 – 255.255.255.255

 

Subnetting IPv4
/31 255.255.255.254 1 Host
/30 255.255.255.252 2 Hosts
/29 255.255.255.248 6 Hosts
/28 255.255.255.240 14 Hosts
/27 255.255.255.224 30 Hosts
/26 255.255.255.192 62 Hosts
/25 255.255.255.128 126 Hosts
/24 255.255.255.0 254 Hosts
/23 255.255.254.0 510 Hosts
/22 255.255.252.0 1022 Hosts
/21 255.255.248.0 2046 Hosts
/20 255.255.240.0 4094 Hosts
/19 255.255.224.0 8190 Hosts
/18 255.255.192.0 16382 Hosts
/17 255.255.128.0 32766 Hosts
/16 255.255.0.0 65534 Hosts
/15 255.254.0.0 131070 Hosts
/14 255.252.0.0 262142 Hosts
/13 255.248.0.0 524286 Hosts
/12 255.240.0.0 1048574 Hosts
/11 255.224.0.0 2097150 Hosts
/10 255.192.0.0 4194302 Hosts
/9 255.128.0.0 8388606 Hosts
/8 255.0.0.0 16777214 Hosts