Factorial Calculator
Calculate the factorial of any number up to 170.
What Is the Factorial Calculator?
A factorial calculator computes n! (n factorial), the product of all positive integers from 1 to n. Factorials grow extremely fast and appear throughout mathematics, especially in combinatorics, probability, and calculus.
The Formula
n! = n x (n-1) x (n-2) x ... x 2 x 1. By definition, 0! = 1.
Example
5! equals 5 times 4 times 3 times 2 times 1, or 120 ways to arrange 5 books on a shelf. 10! comes to 3,628,800, showing how quickly factorials grow. 7! is 5,040 and 12! surpasses 479 million, making these calculations essential for probability and counting problems in statistics.
Common Uses
Permutations and combinations, probability calculations, series expansions in calculus, and binomial theorem.
Frequently Asked Questions
How does the Factorial Calculator work? ▼
Enter your numbers into the input fields and the calculator processes them instantly. Each input has a label explaining what to enter. Results are displayed clearly with context to help you understand them.
Is the Factorial Calculator free? ▼
Yes, all calculators on CalculatorPro Tools are completely free. No registration, no sign-up, and no hidden fees. Just enter your numbers and get results instantly.
Can I trust the accuracy? ▼
Yes, calculations are mathematically exact using standard formulas. We recommend verifying important results independently for critical applications.
Common Mistakes to Avoid
- ⚠ Not double-checking input values before calculating.
- ⚠ Using results for critical decisions without professional verification.
- ⚠ Applying the calculator to situations outside its intended use case.