How do I make a string all lowercase in Python?
We can use Python’s built-in str.lower()
(https://docs.python.org/3/library/stdtypes.html#str.lower) method. This will work regardless of how many uppercase letters the string contains. For example:
print("HELLO WORLD!".lower()) # will output "hello world!" print("Hello World!".lower()) # will output "hello world!" print("hello world!".lower()) # will output "hello world!"
If we’re making our string all lowercase in order to do case-insensitive matching, we may want to use str.casefold()
instead. This method is a more aggressive form of str.lower()
, which includes additional substitutions such as “ss” for the German character “ß”. The workings of this method are implemented in accordance with section 3.13 of the Unicode Standard.