Python String Methods for Whitespace Removal

When working with Python strings, there are times when you'll need to remove unwanted whitespaces, tabs, and newline characters.

You may have to resize strings, or ensure consistency for further processing - such as processing text collected through forms.

And Python's string methods for whitespace removal return strings with all unwanted whitespaces, and tabs removed.

📑Note: I'll use the term whitespaces going forward - whitespaces, tabs, and newlines have all been subsumed in this term 'whitespaces'.

In this tutorial, you'll learn how you can remove leading, trailing, and both leading and trailing whitespaces using the built-in string methods, lstrip(), rstrip(), and strip(), respectively.

How to Use lstrip() to Remove Leading Whitespaces in Python Strings

Let's start with the lstrip() method.

<string>.lstrip() returns a copy of the string with all leading whitespaces removed.

The l in lstrip() stands for left. So this method removes all whitespaces to the left of the first character in the string. Therefore it removes leading whitespaces.

▶ Here's an example. Consider the string " Coding is hard, yet fun!\t" - it has 4 leading whitespaces, and 1 trailing tab (\t).

Now, call the lstrip() method on this string. And store the returned string in the variable l_str.

long_str = "    Coding is hard, yet fun!\t"
l_str = long_str.lstrip()

Let's print out the lengths of the original string long_str, and the returned string l_str. Now, l_str is "Coding is hard, yet fun!\t"

print(len(long_str))
print(len(l_str))

# Output
29
25

As you can see from the lengths, the 4 leading whitespaces have been removed.

How to Use rstrip() to Remove Trailing Whitespaces in Python Strings

Let's now look at the rstrip() method.

<string>.rstrip() returns a copy of the string with all trailing whitespaces removed.

The r in rstrip() stands for right. So this method removes all whitespaces to the right of the last character in the string. Therefore it removes trailing whitespaces.

▶ Let's use the same example string from the previous section. And call the rstrip() method on this string, store the returned string in the variable r_str.

r_str is now " Coding is hard, yet fun!

long_str = "    Coding is hard, yet fun!\t"
r_str = long_str.rstrip()
print(len(long_str))
print(len(r_str))

# Output
29
28

As you can see, the trailing tab \t has been removed. And the returned string's length is one less than the original string—as expected.

How to Use strip() to Remove Leading and Trailing Whitespaces in Python Strings

Now that you know how to remove leading and trailing whitespaces using lstrip() and rstrip() respectively, in this section, you'll learn how strip() method helps remove both leading and trailing whitespaces.

<string>.strip() returns a copy of the string with all leading and trailing whitespaces removed.

▶ As with the earlier sections, let's call the strip() method on the string long_str.

The resultant string s_str is "Coding is hard, yet fun!"

long_str = "    Coding is hard, yet fun!\t"
s_str = long_str.strip()
print(len(long_str))
print(len(s_str))

# Output
29
24

From the length of the returned string, you can see that both the 4 leading whitespaces, and the trailing \t have been removed.

Conclusion

Hope you found this short tutorial on string methods helpful.

The table below summarizes what you've learned:

Happy learning and coding!😄