# How to Iterate Backwards in Python

Muhammad Maisam Abbas Feb 02, 2024

The `range()` function in the `for` loop can also be used to iterate backward by just setting the third parameter to -1 in Python. In this tutorial, we discuss this function further so that you can execute this program too.

## Iterate Backwards With the `range()` Function in Python

The traditional use of the `range()` function with `for` loop is demonstrated in the following coding example:

``````for x in range(0, 10):
print(x)
``````

Output:

``````0
1
2
3
4
5
6
7
8
9
``````

This usage of the `range()` function gives us values that start with 0 and end with 9 with increments of 1 each time. But what if we want to start with 10 and end with 1 with decrements of 1 each time. Luckily for us, the `range()` function already has a solution to this problem.

The `range()` function has a third parameter determining the iterative change in the first value until it reaches the second value. This third parameter is known as a step. We can specify -1 in the step parameter if we want to decrement the first parameter by 1 in each iteration. You can use the following program snippet to iterate backward using the step parameter in the `range()` function:

``````for x in range(10, 0, -1):
print(x)
``````

Output:

``````10
9
8
7
6
5
4
3
2
1
``````

We iterated through 10 to 1 while decrementing by 1 each time with the `range()` function in the code above. This approach is so easy to use and straightforward that there is no need for another approach to achieve this goal.

Maisam is a highly skilled and motivated Data Scientist. He has over 4 years of experience with Python programming language. He loves solving complex problems and sharing his results on the internet.