Check if two strings are equal ignoring case

Two strings are said to be equal ignoring case, if and only if the two strings have same length and same characters (case insensitive) at respective positions.

https://youtu.be/Ff9ZPIpU37g?si=8MFJYHsvZiOk39Qu

To check if two strings are equal ignoring case, convert both the strings to lowercase or uppercase, and compare these using Equal-to Comparison Operator.

Syntax

The syntax of the boolean expression using Equal-to operator to check if the strings str1 and str2 are equal ignoring the case is

str1.lower() == str2.lower()

str1.upper() == str2.upper()

Examples

1. Check if two given strings are equal using lower() method

In the following program, we take same string value in str1 and str2 variables but different case characters, and check if these two strings are equal programmatically ignoring the case using String.lower() method.

Python Program

str1 = 'Hello World'
str2 = 'HELLO WORLD'

if str1.lower() == str2.lower() :
    print('two strings are equal ignoring case')
else :
    print('two strings are not equal ignoring case')

Output

two strings are equal ignoring case

2. Check if two given strings are equal using upper() method

In the following program, we will use String.upper() method to check if str1 and str2 strings are equal ignoring the case.

Python Program

str1 = 'Hello World'
str2 = 'HELLO WORLD'

if str1.upper() == str2.upper() :
    print('two strings are equal ignoring case')
else :
    print('two strings are not equal ignoring case')

Output

two strings are equal ignoring case

3. Negative scenario (different string values)

In the following program, we take different string values in str1 and str2 variables, and check if these two strings are equal or not ignoring the case.

Python Program

str1 = 'Hello World'
str2 = 'HELLO'

if str1.upper() == str2.upper() :
    print('two strings are equal ignoring case')
else :
    print('two strings are not equal ignoring case')

Output

two strings are not equal ignoring case

Summary

In this tutorial of Python Examples, we learned how to check if two strings are equal ignoring the case using String.lower() or String.upper() method, and equal-to operator, with the help of well detailed examples.