Network
IP Subnet Calculator
Network, broadcast, mask, and host range from CIDR.
100% free · runs in your browser · nothing is uploaded.
Why use this tool
- 100% free, forever
- No sign-up or login
- Runs entirely in your browser
- Your files never leave your device
- Unlimited use, no watermarks
- Works on desktop and mobile
How to use IP Subnet Calculator
- 1
Open IP Subnet Calculator — it loads instantly in your browser.
- 2
Enter or upload your input and adjust any available options.
- 3
Copy or download your result. Nothing is uploaded.
Enter an IPv4 address in CIDR notation to compute the network and broadcast addresses, subnet mask, and usable host range.
Frequently asked questions
Yes — IP Subnet Calculator is completely free, with no sign-up, no usage limits, and no watermarks.