Python String isalpha()

Summary: in this tutorial, you’ll learn how to use the Python string isalpha() method to check if all characters in a string are alphabetic.

Introduction to the Python string isalpha() method #

The string isalpha() method returns True if:

• the string contains only alphabetic characters
• and the string has at least one character.

Otherwise, the isalpha() method returns False.

The following shows the syntax of the isalpha() method:

str.isalpha()Copy

Note that alphabetic characters are characters defined as letters in the Unicode character database.

Python string isalpha() method examples #

The following example uses the isalpha() method to check if a string contains alphabetic characters:

name = 'John'
print(name.isalpha())Copy

Output:

TrueCopy

It returned True because the string 'John' contains only alphabetic characters.

The following example returns False because the string 'Jane Doe' contains a space:

name = 'Jane Doe'
print(name.isalpha())Copy

Output:

FalseCopy

In general, if the string contains whitespace, the isalpha() method returns False.

The following example uses the isalpha() method to check if all the characters in the string 'Python3' are alphabetic. It returns False because the string contains a number:

s = 'Python3'
print(s.isalpha())Copy

Output:

FalseCopy

The following example returns False becuase the string is empty:

empty = ''
print(empty.isalpha())Copy

Output:

FalseCopy

Summary #

• Use the Python string isalpha() method to check if all characters in a string are alphabetic.