Network Tools
Calculate the number of usable IPv4 hosts from a CIDR prefix.
Use this Usable Hosts Calculator to find how many usable IPv4 host addresses are available in a subnet based on CIDR notation. It is useful for subnetting practice, network planning, and quick IPv4 calculations.
Use this Usable Hosts Calculator to find how many usable IPv4 host addresses are available in a subnet based on CIDR notation. It is useful for subnetting practice, network planning, and quick IPv4 calculations.
Use usable hosts calculator when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.
Read step-by-step usage guidance, best practices, and common mistakes.
See common questions and answers about input, output, and tool usage.
Review practical input and output examples before running the tool.
Find similar and supporting tools for adjacent actions and follow-up tasks.
Input
24
Output
CIDR: /24 Total Addresses: 256 Usable Hosts: 254
Shows the standard usable host count for a /24 subnet.
Input
30
Output
CIDR: /30 Total Addresses: 4 Usable Hosts: 2
Useful for very small IPv4 subnets.
Fix: Use a CIDR value between 0 and 32.
Fix: This tool is only for IPv4 host calculations.
Fix: Remember usable hosts usually exclude network and broadcast addresses.
It calculates total IPv4 addresses and usable host addresses from a CIDR prefix.
Use a prefix like 24 or /24.
No. This version is for IPv4 only.
Because standard IPv4 subnets reserve one address for the network and one for broadcast.
A /24 subnet has 254 usable IPv4 hosts.