Subnet Calculator
Compute network address, broadcast address, usable hosts and range from an IPv4 address and CIDR prefix.
Input Data
Ip
Prefix
Results
Computed network address.
192.168.1.0
Computed broadcast address.
192.168.1.255
Number of usable host addresses.
254
Explanatory note about the result.
192.168.1.10/24 → 網路 192.168.1.0、廣播 192.168.1.255、可用 254。
At a glance:Given an IPv4 address and prefix p, the network address is the host bits cleared, broadcast is host bits set, and usable hosts = 2^(32−p) − 2. Complements ipv4 and cidr tools.
Formula
Network = ip & mask, where mask = /p.
Usable hosts = 2^(32 − prefix) − 2.
How to Use
- Enter an IPv4 address and CIDR prefix.
- The tool returns network, broadcast, usable hosts and range.
Case Studies
192.168.1.10 /24
Network = 192.168.1.0; broadcast = 192.168.1.255; usable hosts = 254.
FAQ
Why subtract 2 from the host count?
The network and broadcast addresses are reserved and not assignable to hosts.
Related Tools
References
Content review: Calculatorism Network Team. Results are for reference only; please refer to the relevant authorities for the official figures.