CIDR Calculator
Calculate network, broadcast, range, and host count for an IPv4 CIDR.
About this tool
Enter any IPv4 CIDR like 192.168.1.0/24 to get the network address, broadcast address, first/last usable host, total hosts, netmask, and wildcard. All math runs locally — no network calls, no logging.
FAQ
- Why are usable hosts (totalHosts − 2) for /24 but equal to total for /31 and /32?
- Per RFC 3021, /31 networks have no separate network/broadcast addresses (used for point-to-point links). /32 is a host route — a single address.
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