Python String upper() Function

Python String upper() method converts all lowercase characters in a string into uppercase characters and returns it.

Example:

LIST UPPER

What is the String upper() Method?

String upper() is an in-built function in Python, that converts all the letters in a string to uppercase(capital) and then returns it.

It is very useful for standardizing string cases, like when comparing case-insensitive strings.

Python String upper() Syntax

string.upper()

Parameters

• The upper() method doesn’t take any parameters. 

Returns

returns an uppercase string of the given string.

How to Use String upper() Function?

The string upper() function is a simple and easy-to-use function. You just need to call the upper() function with the string object. Let’s understand how to convert string to uppercase(capital) with an example:

CONVERT TO UPPERCASE

Methods to Convert String to Uppercase

There are various ways How to Convert a String to Uppercase in Python, here we are discussing some generally used method for converting a string to uppercase in Python those are as follow.

• Using upper() Method
• Using capitalize() Method
• Using casefold() Method
• String with Case-Insensitive Comparison

1. Convert a String to Uppercase Using upper() Method

Here we are using the string upper() in Python.

In this example, the below code converts the string “geeks for geeks” to uppercase using the `upper()` method, and then prints the result: “GEEKS FOR GEEKS”.

Output

GEEKS FOR GEEKS

2. Convert a String to Uppercase Using capitalize() Method

The `capitalize()` method in Python converts the first character of a string to uppercase and the rest to lowercase, returning the modified string.

Example,: In this example the below code capitalizes the first letter of the string “geeks for geeks” and prints the modified string: “Geeks for geeks”.

Output

Geeks for geeks

3. Convert a String to Uppercase Using casefold() Method

The `casefold()` method in Python converts a string to lowercase and is suitable for case-insensitive comparisons. It is more aggressive than `lower()` and handles a broader range of Unicode characters.

Example 1: In this example the below code converts the string “GeEkS FoR GeEkS” to lowercase using `casefold()` for case-insensitive handling and prints the result: “geeks for geeks.”

Output :

geeks for geeks

4. Uppercase with Case-Insensitive Comparison

This method converts a string to uppercase in Python while allowing case-insensitive comparison by using the `upper()` method for the uniform casing.

Example 1: In this example, we will take GFG as a user input to check for Python String and apply the string upper() function to check for case-sensitive comparison.

Output

Enter your choice: gfg 
You didn't choose 'GFG'.

Example 2: One of the common applications of the upper() method is to check if the two strings are the same or not. We will take two strings with different cases, apply upper() to them, and then check if they are the same or not. In this example the below code checks if two strings (`text1` and `text2`) are the same, ignoring case, and prints the result.

Output

Strings are same

In this article, we have covered the definition, syntax, and use of the upper() function in Python. We have also seen different variations in using the upper() function and other methods to capitalize a string in Python.

upper() function is a very useful function for case-insensitive string comparison operations.

Read Other String Methods

Also Read:

• Python – Uppercase Half String
• Python – Uppercase Selective Substrings in String
• isupper(), islower(), lower(), upper() in Python