Subnet Calculator
Calculate network address, broadcast, usable hosts, and binary breakdown for any IPv4 subnet.
How to use the subnet calculator
Enter any IPv4 address and select a CIDR prefix (e.g. /24) or choose a subnet mask from the dropdown. Click Calculate to instantly get the network address, broadcast address, usable host range, wildcard mask, total hosts, and binary representation.
What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation expresses an IP address and its associated network prefix as a single string — for example 192.168.1.0/24. The number after the slash indicates how many bits are used for the network portion, leaving the remaining bits for host addressing. A /24 gives 254 usable hosts; a /30 gives only 2 — useful for point-to-point links.