IT & Developers
CIDR Calculator
Calculate CIDR notation and IP ranges
Created and maintained by: CalcTago Editorial TeamLast updated: 2026-02-09
Formulas and edge cases are reviewed against authoritative references before publication. For methodology, editorial standards, or corrections, use the links below.
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Frequently asked questions
What does the CIDR Calculator do?
It helps you calculate CIDR notation and IP ranges.
What inputs do I need?
Enter IP address and Prefix length.
Are decimals supported?
Yes, you can use decimal values where appropriate.
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About this tool
This CIDR Calculator turns your inputs into practical results. Provide IP address and Prefix length to calculate Subnet mask and Network address.
Adjust values to compare scenarios and see how sensitive the result is. The calculation uses the numbers as entered, so double-check units and expect small differences from rounding in the displayed totals.