Python String islower() Method Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report The islower() method in Python checks if all characters in a string are lowercase. It returns True if all alphabetic characters are lowercase, otherwise, it returns False, if there is at least one uppercase letter.Let's look at a quick example of using the islower() method. Python s = "hello" res = s.islower() print(res) OutputTrue Explanation: The string s contains only lowercase alphabetic characters, so islower() returns True.Table of ContentSyntax of islower()Example of islower()Frequently Asked Questions on Python String islower()Syntax of islower()s.islower()Parameter:This method doesn't take any parameter.Return Value: The method return True if all alphabetic characters in the string are lowercase, otherwise False.Example of islower()Let’s look at a few examples of islower() method. Python s1 = "hello" res1 = s1.islower() print(res1) s2 = "Hello" res2 = s2.islower() print(res2) s3 = "hello123" res3 = s3.islower() print(res3) s4 = "" res4 = s4.islower() print(res4) s5 = "123@" res5 = s5.islower() print(res5) OutputTrue False True False False Explanation:s1 is "hello": contains only lowercase letters, so islower() returns True.s2 is "Hello": has an uppercase 'H', so islower() returns False.s3 is "hello123": all alphabetic characters are lowercase, so islower() returns True.s4 is "": an empty string returns False by default.s5 is "123@": contains no alphabetic characters, so islower() returns False. At least one lowercase letter is needed for True.Related Articles:Python String isupper() MethodPython String isalpha() MethodPython String isdigit() MethodPython String isalnum() Method Comment More infoAdvertise with us Next Article Python String count() Method M manjeet_04 Follow Improve Article Tags : Python python-string Python-string-functions Practice Tags : python Similar Reads Python String count() Method The count() method in Python returns the number of times a specified substring appears in a string. It is commonly used in string analysis to quickly check how often certain characters or words appear.Let's start with a simple example of using count().Pythons = "hello world" res = s.count("o") print 2 min read Python - Strings encode() method String encode() method in Python is used to convert a string into bytes using a specified encoding format. This method is beneficial when working with data that needs to be stored or transmitted in a specific encoding format, such as UTF-8, ASCII, or others.Let's start with a simple example to under 3 min read Python String endswith() Method The endswith() method is a tool in Python for checking if a string ends with a particular substring. It can handle simple checks, multiple possible endings and specific ranges within the string. This method helps us make our code cleaner and more efficient, whether we're checking for file extensions 2 min read expandtabs() method in Python expandtabs() method in Python is used to replace all tab characters (\t) in a string with spaces. This method allows for customizable spacing, as we can specify the number of spaces for each tab. It is especially useful when formatting text for better readability or alignment. 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Syntax: string.format_map(z) Parameters: Here z is a variable in which the input dictionary is stored and string is the key of the input dictionary. input_dict: Takes a single parame 2 min read Python String index() Method The index() method in Python is used to find the position of a specified substring within a given string. It is similar to the find() method but raises a ValueError if the substring is not found, while find() returns -1. This can be helpful when we want to ensure that the substring exists in the str 2 min read Python String isalnum() Method The isalnum() method is a string function in Python that checks if all characters in the given string are alphanumeric. If every character is either a letter or a number, isalnum() returns True. Otherwise, it returns False. For Example:Pythons = "Python123" res = s.isalnum() print(res)OutputTrue Exp 2 min read Python String isalpha() Method The isalpha() method checks if all characters in a given string are alphabetic. It returns True if every character in the string is a letter and False if the string contains any numbers, spaces, or special characters.Let’s start with a simple example of using isalpha()Pythons1 = "HelloWorld" res1 = 2 min read Like