IP/CIDR Calculator
Network address, broadcast, host range, subnet mask — instantly.
What is an IP Subnet Calculator and How to Use It?
An IP subnet calculator computes network address, broadcast address, usable host range, subnet mask, wildcard mask, and the number of available hosts from a given CIDR notation (e.g. 192.168.1.0/24). Subnetting divides a large IP address space into smaller segments to improve routing efficiency, security, and network management. Both IPv4 and IPv6 are supported.
Frequently Asked Questions
What is CIDR?
CIDR (Classless Inter-Domain Routing) is a notation for specifying subnets, e.g. 192.168.1.0/24. The number after / is the mask length.
How to calculate broadcast address?
Enter IP and subnet mask — the calculator shows network, broadcast, host range, and number of available addresses.
Related guides
Longer-form reading on this topic from the knowledge base.
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