online CIDR and IP subnet calculator : Check host

128.231.4.0-128.231.7.255
128.231.4.0/22

128.231.8.0-128.231.15.255
128.231.8.0/21

128.231.16.0-128.231.31.255
128.231.16.0/20

128.231.32.0-128.231.63.255
128.231.32.0/19

128.231.64.0-128.231.127.255
128.231.64.0/18

128.231.128.0-128.231.191.255
128.231.128.0/18

128.231.192.0-128.231.223.255
128.231.192.0/19

128.231.224.0-128.231.239.255
128.231.224.0/20

128.231.240.0-128.231.243.255
128.231.240.0/22

128.231.244.0-128.231.244.255
128.231.244.0/24

IP subnet calculator 128.231.4.0-128.231.244.255