How to Convert String to List in Python (Space-Separated Words)

To convert a space-separated string to a list in Python, call the str.split() method:

sentence = "This is a test"

words_list = sentence.split()

print(words_list)

Output:

['This', 'is', 'a', 'test']

This works because the str.split() splits the string by blank spaces by default.

Let’s then take a look at how to split a string of integers into a list of integers.

How Does the split() Method Work?

In Python, you can split a string into a list using the split() method. The split() method divides the string into substrings based on a specified separator and returns them as a list.

As an example:

string = "Hello World"
list = string.split() # splits the string using whitespace as the separator
print(list)

Output:

['Hello', 'World']

Here, the split() method is called on the string variable. It returns a list of two elements, which are "Hello" and "World".

By default, the split() method uses whitespace as the separator, but you can specify a different separator by passing it as an argument to the split() method.

For example, if you want to split a string based on a comma separator, you can do this:

string = "apple,banana,orange"
list = string.split(",") # splits the string using a comma as the separator
print(list)

This results in the following output:

['apple', 'banana', 'orange']

Convert String of Integers to a List in Python

To convert a space-separated string of integers to a list in Python:

  1. Split the string into empty spaces.
  2. Convert each element to an integer.
  3. Add each integer to a list.

You can do this with a for loop:

numbers_str = "1 2 3 4 5"

numbers_list = []

for num_str in numbers_str.split():
    num_int = int(num_str)
    numbers_list.append(num_int)

print(numbers_list)

Output:

[1, 2, 3, 4, 5]

To make the expression way shorter, you can use a list comprehension:

numbers_str = "1 2 3 4 5"

numbers_list = [int(num) for num in numbers_str.split()]

print(numbers_list)

Output:

[1, 2, 3, 4, 5]

Further Reading

Python Tricks

Python List Comprehensions