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THE FEUTEX TOOLKIT

IPv4 CIDR Subnet Calculator

Calculate subnet mask, network range and usable addresses from an IPv4 CIDR.

Developer workspace● Runs in your browser
01 Your input
02 Your result

How to use this tool

  1. Paste input in the format shown in the example.
  2. Set the options and run the analysis.
  3. Review the output and any limitations before using the results.

Try this example

192.168.1.20/24

Accuracy and scope

IPv4 only. /31 uses point-to-point interpretation; /32 is a host route. Does not inspect real networks.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.