Subnet calculator
Enter an IPv4 address with a CIDR prefix to calculate the network, broadcast, usable host range, and mask.
What does this calculate?
A CIDR notation like 192.168.1.0/24 describes a block of IP addresses. The number after the slash tells you how many of the 32 bits define the network — the rest belong to hosts inside it. This tool breaks the block down into its network address, broadcast address, subnet mask, wildcard mask, the first and last usable host, total usable host count, and the IP class. Useful when planning a subnet, configuring a firewall, or decoding an ACL rule.
Works on all devices. Blocks ads and trackers. Replaces your default resolver.
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