Combination Calculator

Calculate the number of ways to choose r items from n items where order doesn't matter.

  • Free Online Tool
  • Instant Results
  • Mobile Friendly
  • No Installation
  • Secure & Private

Understanding This Calculator

Combination Formula (nCr)

Selections where order does NOT matter.

C(n, r) = n! / [ r! × (n-r)! ]

Example 1

Choose 2 items from 5 (n=5, r=2)

  • numer: 5! = 120
  • denom: 2! × 3! = 2 × 6 = 12
  • nCr = 120 / 12 = 10

Example 2

Choose 3 from 3 (n=3, r=3)

  • C(3,3) = 1 (Only 1 way to choose all)

How to Use

  • Enter total number of items.
  • Enter how many to choose.

Frequently Asked Questions

How do I use the Combination Calculator (nCr)?

Enter your values in the input fields, and the result will appear instantly.

Is this calculator free to use?

Yes, this calculator is 100% free and does not require any registration or subscription.

Is it mobile-friendly?

Absolutely! Our tool is optimized for all devices, including mobile phones, tablets, and desktop computers.