Formula Explanation
C(n,r) = n! / (r!(n-r)!)
This calculator applies the formula C(n,r) = n! / (r!(n-r)!). Enter each value with the matching unit, and AZCalculate updates the result instantly.
Mathematics
Combination Calculator
Use this combination calculator to calculate calculate combinations where order does not matter.
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Calculator
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Calculator Inputs
Choose what you want to calculate, enter realistic values, adjust units where shown, and use the scenario section for repeated-use planning.
Input and Formula Breakdown
This calculator applies the formula C(n,r) = n! / (r!(n-r)!). Enter each value with the matching unit, and AZCalculate updates the result instantly.
Total items n
10
Selected items r
3
Combinations
120
Scenario and Comparison
Current
120
Projected
1,440
Adjusted
132
Visual Comparison
Current result120
Projected usage1,440
Comparison scenario132
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Use Cases
- Count selections
- Study probability
- Plan groups
Step-by-Step Explanation
- Step 1Enter the known values in the calculator fields.
- Step 2Keep the units consistent with the labels shown beside each input.
- Step 3Apply the formula: C(n,r) = n! / (r!(n-r)!).
- Step 4Review the primary result and supporting values.
Example calculation
Example combination calculator
Given
- Total items n: 10
- Selected items r: 3
Steps
- Use the values shown above.
- Apply C(n,r) = n! / (r!(n-r)!).
Result
The calculator above shows the computed answer instantly from these example values.
Calculator guide
About this Combination Calculator
Calculate combinations where order does not matter. This page includes an interactive calculator, concise formula notes, worked examples, FAQs, related calculators, and practical guidance you can revisit whenever needed.
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Calculator usage
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Live users now
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Total saved calculations
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Most active date
2026-06-05
FAQ
Combination Calculator FAQs
How does the combination calculator work?+
It uses C(n,r) = n! / (r!(n-r)!) and calculates the result from the values you enter.
Can I copy or print the result?+
Yes. AZCalculate calculator pages include copy, share, and print actions.
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