Factorial
Compute the factorial n! of an integer up to 170, helping you solve combinatorial problems and probability calculations directly in your browser.
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Factorial
The factorial calculator computes the factorial n! of an integer, meaning the product of all positive integers from 1 to n. It supports values up to 170 and is an indispensable tool for combinatorial problems and probability calculations. The computation happens directly in your browser without you having to laboriously multiply the values by hand.
How it works
The factorial of n, written as n!, is the product of all positive integers from 1 to n. The formula is: n! = 1 × 2 × 3 × ... × n. By definition, 0! = 1, which is the empty product. As a concrete example, 5! = 1 × 2 × 3 × 4 × 5 = 120. And 7! = 1 × 2 × 3 × 4 × 5 × 6 × 7 = 5040. The calculator accepts integers and computes the product automatically. It supports factorials up to 170, since 170! is already an extremely large number that falls into the floating-point range.
What the tool can and cannot do
This calculator supports only integers from 0 through 170. It cannot compute factorials of negative numbers because the factorial is not defined for negative numbers. For values above 170 the result is too large and cannot be represented as a floating-point number. The calculator is a pure computation utility and does not directly offer combinatorial functions like binomial coefficients or permutations. It does not compute the gamma function for non-integer arguments, only the classical factorial of integers.
Why local processing in the browser
All calculations happen locally in your browser. Your inputs are never sent to a server, there is no upload and no server log files storing your data. You need no account and do not need to register. After the page loads, the calculator works offline too, because the assets are cached in the browser. There is no attackable server and nothing is transmitted over the network. You can freely calculate, discard results, and enter new values as often as you like, because nothing is stored or tracked. Local processing also means the data does not need to be sent over a network, reducing energy consumption.
Frequently asked questions
What is the factorial of 0?
The factorial of 0 is defined as 1. This is the empty product and serves as the base case for the recursive definition of the factorial.
Do I need to be online?
No, the calculator works offline after the page loads. The computation is purely local and requires no Internet connection.
Are my data uploaded?
No, all inputs stay on your device. There is no upload, no server logs, and no third-party access to your data.
Up to which number can I calculate?
The calculator supports factorials from 0 through 170. For 170! the result is already an extremely large number that approaches the limits of floating-point numbers.
Can I enter negative numbers?
No, the factorial is not defined for negative numbers. The calculator accepts only nonnegative integers.
What is the factorial used for in practice?
The factorial is used in practice for combinatorics, probability theory, permutations, and many other mathematical applications.