IP Subnet Calculator
Calculate network address, broadcast, and host ranges for any IP/CIDR
/0/8/16/24/32
Quick Presets
Invalid IP address or CIDR. Please enter a valid IPv4 address.
Understanding IP Subnets
Network Address
The first IP in a subnet - identifies the network itself. Cannot be assigned to hosts.
Broadcast Address
The last IP in a subnet - used to send data to all hosts on the network.
Subnet Mask
Defines which portion of the IP identifies the network vs the host.
CIDR Notation
Compact way to express subnet size - the number of network bits (e.g., /24 = 255.255.255.0).