Factorials with Loops

Find the factorial of a number using a while loop.

A factorial of a whole number is that number multiplied by every whole number between itself and 1. For example, 6 factorial (written "6!") equals 6 x 5 x 4 x 3 x 2 x 1 = 720. So 6! = 720.

# number to find the factorial of
number = 6
# start with our product equal to one
product = 1
# track the current number being multiplied
current = 1

while  current <= number:
    # multiply the product so far by the current number
    product *= current
    # increment current with each iteration until it reaches number
    current += 1


# print the factorial of number
print(product)

Find the factorial of a number using a for loop.

# number we'll find the factorial of
number = 6
# start with our product equal to one
product = 1

# calculate factorial of number with a for loop
for num in range(2, number + 1):
    product *= num

# print the factorial of number
print(product)