Lowercase a String in Python

How do I lowercase a string in Python?

With my experience in Python programming, I’ve found the lower() method to be quite efficient:


my_string = "Hello, World!"

lowercase_string = my_string.lower()

print(lowercase_string)

This method works well for most standard cases.

From my time working on various Python projects, I’ve learned that you can also use list comprehension to achieve this:


my_string = "Hello, World!"

lowercase_string = ''.join([char.lower() for char in my_string])

print(lowercase_string)

This approach gives you more control over the characters if you need it.

Based on my extensive experience with Unicode data in Python, I recommend using the str.casefold() method. It’s similar to lower() but is designed to be more aggressive in handling Unicode characters:


my_string = "Hello, World!"

lowercase_string = my_string.casefold()

print(lowercase_string)

This is particularly useful for internationalized applications.