MihsabaHow to use
The factorial n! is the product of the positive integers from 1 through n. This calculator uses exact big-integer arithmetic so large results are not rounded.
- Enter a non-negative integer from 0 to 2000.
- Calculate to get the full exact n! value.
- Review its digit count, trailing zeros and scientific summary.
How it is calculated
n!=1×2×…×n, with 0!=1
Example
5! = 5×4×3×2×1 = 120. By convention, 0! = 1.
Important notes
Factorials grow extremely quickly, so the exact result can become very long even though it remains exact up to 2000! here.
Frequently asked questions
Why is 0! equal to 1?
It is the empty-product convention and keeps factorial identities consistent.
Are large factorials rounded?
No. The main n! output is an exact integer.
Can I enter negative or decimal values?
Not for the ordinary factorial definition used here.
Is this calculator free?
Yes. It is free to use and requires no account.