CIDR calculator
Runs entirely in your browser. Useful for reading IP reports, ACLs, and route announcements.
Result
Canonical CIDR
18.64.152.0/21
Version
IPv4
Prefix
/21
Network
18.64.152.0
Broadcast
18.64.159.255
First address
18.64.152.1
Last address
18.64.159.254
Netmask
255.255.248.0
Wildcard
0.0.7.255
Total addresses
2048
Usable hosts
2046