CIDR Calculator
Last updated: 2026 · Free online tool
What is CIDR Calculator?
Free online CIDR calculator that takes a block like 192.168.0.0/24 and computes the network address, IP range, usable host count, broadcast address and subnet mask for fast subnet planning.
How to Use
- 1 Input — Enter the required data.
- 2 Results — Review the calculated results.
- 3 Copy — Copy the results to use.
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Frequently Asked Questions
A free online tool that calculates IP ranges and subnets using CIDR notation.
Yes, it is completely free.
No. All processing happens in your browser.
Yes, the responsive design works on mobile devices.
Yes, it works offline as it uses static data.