/24 = 256 IPv4 addresses
/23 = 512 IPv4 addresses
/22 = 1024 IPv4 addresses
/21 = 2048 IPv4 addresses
/20 = 4096 IPv4 addresses
/19 = 8192 IPv4 addresses
/18 = 16384 IPv4 addresses
/17 = 32768 IPv4 addresses
/16 = 65536 IPv4 addresses
/15 = 131 072 IPv4 addresses
/14 = 262144 IPv4 addresses