IP Range Calculator

Inspect range size, classify endpoints, and summarize the smallest CIDR blocks that exactly cover an IPv4 interval.

Start IPv4

End IPv4

—Addresses

—Exact CIDR blocks

—Start type

—End type

ReadyThe CIDR summary exactly covers the selected interval.

How to use this IP Range Calculator

Calculate the IPv4 range covered by a start and end address. Enter your values above and the result is calculated directly in your browser. No account is required.

Fast answer, clear inputs

This tool is built around one job: give the answer quickly without forcing a signup or hiding the result. Related tools are linked nearby when the next calculation or conversion is useful.