Example: 10.0.0.0 with /8, or 203.0.113.50/29—any host address in the block works.
Enter any IPv4 inside the subnet and a prefix length (0–32). Outputs mask, network, broadcast, and host range.
Example: 10.0.0.0 with /8, or 203.0.113.50/29—any host address in the block works.
No—this page is IPv4 dotted-decimal and CIDR only.
/31 is often used for point-to-point links (RFC 3021) with two usable addresses. /32 is a single-host route.
All math runs locally in your browser; nothing is sent to our server.
Use it as a quick check. Real designs need your org’s addressing plan, VLSM rules, and device capabilities.
No. Educational tool only.
Inputs stay on your device unless your browser or extensions do otherwise.