IP / CIDR Calculator
Enter an IP address with CIDR prefix (e.g. 192.168.1.0/24) and instantly get the network address, broadcast address, subnet mask, total hosts, usable host range, and wildcard mask.
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What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation combines an IP address with a prefix length like /24 to define a network. /24 means the first 24 bits are the network portion, leaving 8 bits (256 addresses) for hosts.
How many usable hosts does /24 give?
A /24 subnet has 256 total addresses. Two are reserved (network and broadcast), leaving 254 usable host addresses.