Python String isupper() Function

By / August 6, 2022

String in Python has built-in functions for almost every action to be performed on a string. Python String isupper() function checks if all the characters in a string are uppercase then returns true else false.

Key Points :

  • Return Type: Boolean i.e. True or False
  • Parametric Values: No Parameters required
  • It is not space-sensitive but case sensitive
  • Empty String also returns False.

String isupper() Syntax

str_name.isupper()

The str_name here refers to the input string. And, isupper() is inbuilt string function in python.

str_name = "WELCOME"
print(str_name.isupper())   # True

String isupper() Examples

Different cases are given below.

Case 1: Every character in a string is uppercase also contains whitespaces/numbers/special characters

str_name = "WELCOME PYTHON USER"
print(str_name.isupper())   # True

str_name = "WELCOME 2019"
print(str_name.isupper())   # True

str_name = "WELCOME @ 2020"
print(str_name.isupper())   # True

Case 2: String contains only numbers or special characters

str_name = "2020"
print(str_name.isupper())   # False

str_name = "@$&"
print(str_name.isupper())   # False

Case 3: Every character in a string is lowercase also contains whitespaces/numbers/special characters

str_name = "welcome python user"
print(str_name.isupper())   # False

str_name = "welcome 2019"
print(str_name.isupper())   # False

str_name = "welcome @ 2020"
print(str_name.isupper())   # False

Case 4: Only the first character of every word is uppercase also contains whitespaces/numbers/special characters

str_name = "Welcome"
print(str_name.isupper())   # False

str_name = "Welcome Python User"
print(str_name.isupper())   # False

str_name = "Welcome 2019"
print(str_name.isupper())   # False

str_name = "Welcome @ 2020"
print(str_name.isupper())   # False

Case 5: String is Empty

str_name = ' '
print(str_name.isupper())   # False

Program to Print List of All Possible Uppercase Characters in Python

The Unicode module can be used to check the uppercase characters. The program is to print all uppercase Unicode characters.

import unicodedata

total_count = 0
for i in range(2 ** 16):
    charac = chr(i)
    if charac.isupper():
        print(u'{:04x}: {} ({})'.format(i, charac, unicodedata.name(charac, 'UNNAMED')))
        total_count = total_count + 1
print("Total Count of Unicode UPPERCASE Characters = ",total_count)
Output All Uppercase Unicode Characters
Output All Uppercase Unicode Characters

It is just a glance of output as the actual output is lengthy. There are 999 Uppercase characters in Unicode.

References