Subnet Calculator
Calculate network, broadcast, host range, and mask from an IPv4 CIDR.
About the Subnet Calculator
Enter an IPv4 address with a CIDR prefix to instantly see the network address, broadcast address, usable host range, subnet mask, wildcard mask, and total host count — plus a binary breakdown of the address and mask.
Examples
/24 network
192.168.1.10/24Output
Network 192.168.1.0, Broadcast 192.168.1.255, 254 hostsKeyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Read more
- Subnetting and CIDR explained without the headache
What a /24 actually means, how to calculate usable hosts, and how to read a CIDR range without a lookup table.
Version 1.0.0 · Updated 2026-08-06 · Runs entirely in your browser