Convert a list of strings into a list of integers in Python

This post will discuss how to convert a list of strings into a list of integers in Python.

For example, list ["1", "2", "3", "4", "5"] should be converted into list [1, 2, 3, 4, 5].

1. Using `map()` function

The recommended solution is to call the built-in function map() to efficiently convert a list of strings into a list of integers. It applies the specified function to every item of the list, yielding the results. Since it returns an iterator, convert the result to a list. This function is demonstrated below:

if __name__ == '__main__':

strings = ["1", "2", "3", "4", "5"]

nums = list(map(int, strings))

print(nums) # prints [1, 2, 3, 4, 5]

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Note that the above code creates a new list. You can mutate the existing list in-place by assigning to the slice [:], as shown below:

if __name__ == '__main__':

nums = ["1", "2", "3", "4", "5"]

nums[:] = list(map(int, nums))

print(nums) # prints [1, 2, 3, 4, 5]

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2. Using List Comprehension

Another approach is to use list comprehension. List comprehension is often used in Python to construct a new list, where each list element results from some operation applied to each member of an iterable.

Here’s a working example using list comprehension:

if __name__ == '__main__':

strings = ["1", "2", "3", "4", "5"]

nums = [int(s) for s in strings]

print(nums) # prints [1, 2, 3, 4, 5]

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That’s all about converting a list of strings into a list of integers in Python.

Convert a list of strings into a list of integers in Python

1. Using map() function

2. Using List Comprehension

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1. Using `map()` function