How to Use the Factorial Calculator
Factorials appear in everything from card game probabilities to advanced calculus. This calculator computes factorials instantly up to 170.
Step-by-Step Instructions
- 1 Enter a non-negative integer (0-170).
- 2 Click Calculate to see the factorial result.
- 3 Values above 170 exceed JavaScripts maximum safe integer and are marked as too large.
Understanding the Inputs
Number
A non-negative integer (0-170) to compute the factorial of. Entering 10 computes 10! = 3,628,800. The maximum supported value is 170 due to JavaScript number precision limits.
How to find it: Common values: 52! calculates the number of ways to shuffle a deck of cards, 20! for basic combinatorics problems.
Why it matters: Factorials grow faster than exponential functions. 10! is over 3.6 million, while 20! is over 2.4 quintillion. This rapid growth limits practical computation to n=170 in standard JavaScript.
Type: number · Default: 0
Tips & Best Practices
- ✓ 52! is approximately 8 x 10^67, which is roughly the number of atoms in the Milky Way galaxy.
- ✓ Factorials are used in the binomial coefficient formula: n choose r = n! / (r! x (n-r)!).
- ✓ Stirlings approximation provides a good estimate for large factorials.
by CalculatorPro Tools · Updated 2026-07-29