Python String isdigit() Method

The isdigit() method returns True if all characters in a string are digits or Unicode char of a digit. If not, it returns False.

Syntax:

str.isdigit()

Parameters:

None.

Return Value:

Returns True if all characters in the string are digits and returns False even if one character is not a digit.

The following examples demonstrate isdigit() method.

mystr = '12345'
print(mystr.isdigit())

mystr = '10.5'
print(mystr.isdigit())

mystr = 'python'
print(mystr.isdigit())

True
False
False

The isdigit() method will return False if the string contains whitespaces, symbols, or alphabets.

print('$100'.isdigit())

print('100 '.isdigit())

False
False

Superscript and subscripts (usually written using Unicode) are also considered digit characters. Hence, if the string contains these decimal characters, the isdigit() returns True. The mentioned Unicode characters should have a numerical output. If the Unicode values do not return a digit, then isdigit() method returns False.

num = '\u0038' # Unicode char for 8
print(num.isdigit())

mystr = '\u00380061'  # Unicode char 8a
print(mystr.isdigit())

arabic_six = '۶' # Arabic digit 6
print(arabic_six.isdigit())

True
False
True

The following table lists difference among the isdecimal(), isdigit(), and isnumeric() methods based on the given inputs: