Network tools / Subnetting
CIDR & Subnet Calculator
Turn an IPv4 address and prefix into a complete network plan, then split the range into smaller subnets.
/24
/24
Network bitsHost bits
Total addresses256
Usable hosts254
Click any result to copy it. /31 networks are treated as point-to-point links, where both addresses are usable.
Split this network
Preview smaller subnets inside the current range.
/26
4 subnets64 addresses each
What does CIDR mean?
CIDR notation combines an IP address with a prefix length. For example, /24 reserves 24 bits for the network and leaves 8 bits for host addresses, producing 256 total IPv4 addresses.