IPv4 subnet calculator

Calculate IPv4 network boundaries and host counts, including explicit /31 point-to-point and /32 handling.

Your input

Outputs are cleared when the input changes.

Result

Enter your data or use the example, then run the tool.

Worked example

192.168.1.130/24 spans .0–.255 with 254 traditional host addresses. /0 returns a summary, not every IP.

Method

Use unsigned integer arithmetic to apply the mask and wildcard. Traditional subnets exclude network and broadcast endpoints.

Limits

No scanning, geolocation or routing assessment. /31 counts both point-to-point endpoints; /32 is a single host route.

Sources

RFC 3021: /31 point-to-point

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