Find Factorial of a Number in PHP using For Loop & Recursion

How to calculate factorial of a number in PHP. In this tutorial, I am going to discuss factorial program in PHP using recursion as well as iterative approach.

Before solving this problem let’s understand what is factorial?

What is Factorial?

Factorial of a non-negative integer n (n!), is the product of all positive integers less than or equal to n.

For example –

5! = 5 * 4 * 3 * 2 * 1 = 120

4! = 4 * 3 * 2 * 1 = 24