Calculators
Factorial Calculator
Calculate the exact factorial of a whole number from 0 to 200 locally in your browser.
Enter a whole number from 0 to 200 to see its exact factorial, digit count, and trailing zeros. The calculation runs locally in your browser; your value is not uploaded or stored.
Find an exact factorial without uploading anything.
Enter a whole number from 0 to 200 to see its exact factorial value, digit count, and trailing zeros. Everything runs locally in your browser, so your value is not uploaded or stored.
Frequently Asked Questions
Everything you need to know about this tool, how it works, and privacy.
What is a factorial?
The factorial of a whole number n, written n!, is the product of every whole number from 1 through n. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120. By definition, 0! = 1.
What does the factorial calculator show?
Enter a whole number from 0 to 200. The calculator returns the exact factorial value, the number of digits, and the number of trailing zeros. For example, 5! = 120 has 3 digits and 1 trailing zero.
Which inputs are accepted?
Enter a whole number from 0 to 200 without decimals or extra characters. Values below 0 or above 200 show a clear error: negative numbers have no factorial in this tool, and larger values are rejected so the exact result stays fast to display.
Do my numbers stay private?
Yes. The calculation and copy action run locally in your browser. CodeASystem does not upload or store the value you enter.