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About CIDR Calculator
CIDR Calculator — free, private, browser-based network tool
Inspect any CIDR block — network, broadcast, hosts, mask, and binary. It runs in your browser, so the file is processed on your own device.
Why use CIDR Calculator
- ·Files stay on your device — nothing is uploaded
- ·No signup needed
- ·Works in any modern browser, on any OS
- ·Free daily use; Pro removes limits and watermarks
How to use it
- 1Type or paste your input.
- 2Pick the options you want.
- 3Copy or save the result.
What CIDR Calculator does
Inspect any CIDR block — network, broadcast, hosts, mask, and binary.
How it works
Local subnet math; server-side DNS/WHOIS via our edge with anti-abuse pacing. The processing code runs inside the page, so your file is not uploaded to a server — you can confirm this in your browser's DevTools → Network tab.
Frequently asked questions
Does CIDR Calculator upload my files?+
No. CIDR Calculator runs in your browser and processes the file on your device. Nothing is sent to our servers.
Is CIDR Calculator free?+
Yes, with a daily free allowance and no signup. Xonvert Pro ($4.99/month) removes the daily limits and the watermark on exported files.
Do I need to install anything?+
No. It works in any modern browser on Windows, macOS, Linux, ChromeOS, Android and iPad.
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