← All tools

IPv4 Range to CIDR

Cover an inclusive IPv4 range with the smallest aligned CIDR blocks.

Input

Input stays in this browser. Nothing is uploaded or stored.

Result

Run the tool to see its result here.

How to use this tool

Enter start and end addresses on separate lines, then review every block before changing firewall rules.

When not to use it

CIDR math does not validate access policy or ownership of public addresses.