How To Remove Characters from a String in Python

Introduction

This article describes two common methods that you can use to remove characters from a string using Python:

• the String replace() method
• the String translate() method

To learn some different ways to remove spaces from a string in Python, refer to Remove Spaces from a String in Python.

A Python String object is immutable, so you can’t change its value. Any method that manipulates a string value returns a new String object.

The examples in this tutorial use the Python interactive console in the command line to demonstrate different methods that remove characters.

Remove Characters From a String Using the replace() Method

The String replace() method replaces a character with a new character. You can remove a character from a string by providing the character(s) to replace as the first argument and an empty string as the second argument.

Declare the string variable:

s = 'abc12321cba'

Replace the character with an empty string:

print(s.replace('a', ''))

The output is:

Output
bc12321cb

The output shows that both occurrences of the character a were removed from the string.

Remove Newline Characters From a String Using the replace() Method

Declare a string variable with some newline characters:

s = 'ab\ncd\nef'

Replace the newline character with an empty string:

print(s.replace('\n', ''))

The output is:

Output
abcdef

The output shows that both newline characters (\n) were removed from the string.

Remove a Substring from a String Using the replace() Method

The replace() method takes strings as arguments, so you can also replace a word in string.

Declare the string variable:

s = 'Helloabc'

Replace a word with an empty string:

print(s.replace('Hello', ''))

The output is:

Output
abc

The output shows that the string Hello was removed from the input string.

Remove Characters a Specific Number of Times Using the replace() Method

You can pass a third argument in the replace() method to specify the number of replacements to perform in the string before stopping. For example, if you specify 2 as the third argument, then only the first 2 occurrences of the given characters are replaced.

Declare the string variable:

s = 'abababab'

Replace the first two occurrences of the character with the new character:

print(s.replace('a', 'A', 2)) # perform replacement twice

The output is:

Output
AbAbabab

The output shows that the first two occurrences of the a character were replaced by the A character. Since the replacement was done only twice, the other occurrences of a remain in the string.

Remove Characters From a String Using the translate() Method

The Python string translate() method replaces each character in the string using the given mapping table or dictionary.

Declare a string variable:

s = 'abc12321cba'

Get the Unicode code point value of a character and replace it with None:

print(s.translate({ord('b'): None}))

The output is:

Output
ac12321ca

The output shows that both occurrences of the b character were removed from the string as defined in the custom dictionary.

Remove Multiple Characters From a String using the translate() method

You can replace multiple characters in a string using the translate() method. The following example uses a custom dictionary, {ord(i): None for i in 'abc'}, that replaces all occurrences of a, b, and c in the given string with None.

Declare the string variable:

s = 'abc12321cba'

Replace all the characters abc with None:

print(s.translate({ord(i): None for i in 'abc'}))

The output is:

Output
12321

The output shows that all occurrences of a, b, and c were removed from the string as defined in the custom dictionary.

Remove Newline Characters From a String Using the translate() Method

You can replace newline characters in a string using the translate() method. The following example uses a custom dictionary, {ord('\n'): None}, that replaces all occurrences of \n in the given string with None.

Declare the string variable:

s = 'ab\ncd\nef'

Replace all the \n characters with None:

print(s.translate({ord('\n'): None}))

The output is:

Output
abcdef

The output shows that all occurrences of the newline character \n were removed from the string as defined in the custom dictionary.

Conclusion

In this tutorial, you learned some of the methods you can use to remove characters from strings in Python. Continue your learning about Python strings.