CIDR calculator
Runs entirely in your browser. Useful for reading IP reports, ACLs, and route announcements.
Result
Canonical CIDR
34.191.0.0/21
Version
IPv4
Prefix
/21
Network
34.191.0.0
Broadcast
34.191.7.255
First address
34.191.0.1
Last address
34.191.7.254
Netmask
255.255.248.0
Wildcard
0.0.7.255
Total addresses
2048
Usable hosts
2046