IP Subnet Calculator
IPv4 subnet — network, broadcast, host range, wildcard mask, usable hosts from CIDR.
How to Use
- Enter an IPv4 address and CIDR prefix (0-32).
- All subnet fields update live.
Show Work
Notes
About the IP Subnet Calculator
IP Subnet Calculator is a quick, free tool for everyday maths and number work. It works in your browser and keeps everything on your device. IPv4 subnet — network, broadcast, host range, wildcard mask, usable hosts from CIDR.
How it works
Enter your figures and the result appears instantly, updating the moment you change anything. There is no submit button and nothing to wait for, so it is easy to try a few what-if numbers and compare the results. Just check each box holds the kind of value it expects.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
How do I use the IP Subnet Calculator?
Simply type your numbers and read the result, which refreshes the instant you change something. There is nothing to submit and nothing to wait for.
Does it cost anything or need an account?
No. The tool is completely free, there is no account to create, and it keeps working offline after the page first loads.
Is anything I type uploaded?
No. The tool works entirely on your device, so the values you enter never leave your browser.
Common Use Cases
Get an answer fast
Type what you have and get the answer in seconds — on a phone, tablet, or computer.
Try different numbers
Change one thing and watch the answer change. It is an easy way to compare your choices.
Nothing to set up
Open the page and start. There is nothing to install, and no account to make.
Stays on your device
Your inputs never leave the browser — nothing is uploaded, logged, or stored anywhere.
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