How to use this combination calculator
Enter the values requested above and select Calculate. Change any input to compare another scenario. The calculation runs locally in your browser and does not require an account.
Formula and method
Example
Choosing 3 people from a group of 10 gives 10C3 = 120 possible groups.
Tips for a useful result
Combinations ignore ordering; use the permutation calculator when order matters.
What this calculator is useful for
Calculate combinations nCr: the number of ways to choose r items from n when order does not matter. The result is intended for quick estimates, checking arithmetic and comparing scenarios. When a result affects a contract, tax filing, medical decision, building-code requirement or other high-stakes situation, verify the result with the appropriate professional or authoritative source.
Frequently asked questions
What does the Combination Calculator calculate?
Calculate combinations nCr: the number of ways to choose r items from n when order does not matter.
How does the Combination Calculator work?
nCr = n! ÷ (r!(n−r)!).
Is the Combination Calculator free to use?
Yes. ERICH Calculators is free to use and does not require an account.