Python String isascii() Method

The isascii() method returns True if the string is empty or all characters in the string are ASCII.

ASCII stands for American Standard Code for Information Interchange. It is a character endcoding standard that uses numbers from 0 to 127 to represent English characters. For example, ASCII code for the character A is 65, and 90 is for Z. Similarly, ASCII code 97 is for a and 122 is for z. ASCII codes also used to represent characters such as tab, form feed, carriage return, and also some symbols. ASCII characters have code points in the range U+0000-U+007F.

Syntax:

str.isascii()

Parameters:

None.

Return Value:

Returns True if a string is ASCII, else returns False.

The following example demonstrates the isascii() method.

mystr = 'ABC'
print(mystr.isascii())

mystr = '012345'
print(mystr.isascii())

mystr = 'ABC'
print(mystr.isascii())

True
True
True

An empty string, new line characterm symbols and numbers are also ASCII characters.

mystr = '#'
print(mystr.isascii())

mystr = '$'
print(mystr.isascii())

mystr = ''
print(mystr.isascii())

mystr = '\n'
print(mystr.isascii())

True
True
True
True

The isascii() method also checks Unicode chars of ASCII, as shown below.

mystr = '/u0000' # Unicode of Null
print(mystr.isascii())

mystr = '/u0041' # Unicode of A
print(mystr.isascii())

mystr = '/u0061'  # Unicode of a
print(mystr.isascii())

mystr = '/u007f' # Unicode of DEL
print(mystr.isascii())

True
True
True
True

The isascii() method returns False for any non-ASCII characters.

mystr = '/u00e2' # Unicode of â
print(mystr.isascii())

mystr = '/u00f8' # Unicode of ø
print(mystr.isascii())

mystr = 'õ'  
print(mystr.isascii())

mystr = 'Å' 
print(mystr.isascii())

mystr = 'ß'   # German letter
print(mystr.isascii())

False
False
False
False
False