Skip to content
Calculation Machine

Factorial Calculator

n! and related combinatorics.

Reviewed by the Calculation Machine team · How we check our maths

Your values

ⓘ Live results

Results
10!
3,628,800
Digits
7
(n−1)!
362,880
Scientific notation
3.628800e+6

Quick answer

n factorial is the product of all whole numbers from 1 to n, and 0! is defined as 1.

The formula

n! = n × (n−1) × … × 1

Worked example

Worked example

Using the values the calculator loads with.

Inputs

  • n10

Result

  • 10!3,628,800
  • Digits7
  • (n−1)!362,880
  • Scientific notation3.628800e+6

How to use the Factorial Calculator

  1. 1Enter a whole number between 0 and 170.
  2. 2Read the factorial and its digit count.
  3. 3Use permutation or combination tools for arrangements.

Frequently asked questions

Why is 0! = 1?

There is exactly one way to arrange nothing, and it keeps combinatorics formulas consistent.

Why cap at 170?

171! exceeds the largest number JavaScript can represent.

About this calculator