Factorial Calculator
Calculate n! for non-negative integers from 0 to 170. See the exact factorial value, digit count, and multiplication steps.
Enter whole numbers from 0 to 170. Use a big integer calculator for larger factorials.
Calculation
What this factorial calculator does
English search intent for a factorial calculator is direct: enter a whole number n, get n!, and see enough steps to check the multiplication.
n must be a non-negative integer. The special case 0! equals 1 by definition.
- Use it for classroom checks, permutations, combinations, and quick combinatorics work.
- The calculator shows the exact integer up to.
- Decimal and negative inputs are rejected because this page does not evaluate the gamma function.
Common factorial values
| n | n! |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 5 | 120 |
| 10 | 3,628,800 |
| 20 | 2,432,902,008,176,640,000 |
Frequently Asked Questions
Sources and References
Calculations are based on the listed reference sources. Links open in a new tab.
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