Embed the CIDR calculator

Add a compact, privacy-friendly IPv4 calculator to your documentation, course, or technical website.

Preview

Copy this HTML into your page. The widget performs calculations in the visitor's browser.

<iframe src="https://cidrtools.net/embed/cidr/" title="CIDR calculator" width="100%" height="380" loading="lazy"></iframe>

Keep the CIDRtools attribution visible. Do not present the widget as a security boundary or a replacement for production configuration review.