Network / IP

Subnet Calculator

Calculate network, broadcast, subnet mask, and usable hosts from IPv4/CIDR.

What is Subnet Calculator for?

Subnet Calculator turns an IPv4/CIDR into practical network details: network address, broadcast, mask, wildcard, and usable host count.

Recommended workflow

  1. Enter an IPv4 address with CIDR prefix, such as 192.168.1.0/24.
  2. Review network, broadcast, subnet mask, and usable host count.
  3. Use the range to check network plans or firewall rules.

How this tool works

Network tools normalize IP, CIDR, host, or URL input, then calculate ranges or inspect live response metadata. They are useful for checking routing assumptions, allowlists, response headers, redirects, and public network ownership.

Part of this tool group

Open nearby tools in the same group to cross-check, inspect deeper, or complete a small workflow.

Open Network / IP hub

Frequently asked questions

What are usable hosts?

Usable hosts are addresses that can be assigned to devices, usually excluding network and broadcast addresses in traditional IPv4 subnets.

A few nearby utilities you can open quickly when you need to check more.

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