Local developer utility

IPv4 CIDR Calculator

Calculate IPv4 network, usable range, and broadcast address locally. Your input stays in your browser while you work.

CIDR Calculator🔒 Processed locally

How to use CIDR Calculator

Complete the labeled fields above, choose an action, and inspect the result before copying or downloading it.

Processing runs locally in this browser. No input is uploaded or sent to a conversion service.

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