Subnet Calculator
Subnet / CIDR Calculator
Enter an IPv4 address and a prefix to get the network and broadcast address, host range, usable hosts, netmask and wildcard. Runs entirely in your browser.
/24
/0/8/16/24/32
Network (CIDR)
Class CPrivate
Addresses
Network
Broadcast
First host
Last host
Mask & count
Netmask
Wildcard
Total addresses
Usable hosts
Binary
Network: 11000000.10101000.00000001.00000000
Netmask: 11111111.11111111.11111111.00000000
About subnetting
Read a subnet at a glance
The three numbers network engineers reach for first.
CIDR notation
The /24 suffix tells you how many bits define the network β the rest are hosts.
Netmask & wildcard
The netmask marks network bits; the wildcard is its inverse, used in ACLs.
Usable hosts
Total addresses minus the network and broadcast give the hosts you can assign.
Frequently asked questions