Factorial Calculator
Calculate the factorial of a number (n!). Also shows permutations and combinations with a second input.
Factorial N
3,628,800
Factorial R6
Factorial, Permutations, and Combinations
Factorial
n! = n × (n-1) × (n-2) × ... × 2 × 1
0! = 1 by convention.
Permutations (order matters)
P(n, r) = n! / (n-r)!
Number of ways to arrange r items from n distinct items.
Combinations (order doesn't matter)
C(n, r) = n! / (r! × (n-r)!)
Number of ways to choose r items from n without regard to order.
Example Calculation
Calculate 10!, P(10,3), and C(10,3).
- 0110! = 3,628,800
- 02P(10,3) = 10!/7! = 10×9×8 = 720
- 03C(10,3) = 720/3! = 720/6 = 120
Frequently Asked Questions
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