Python String islower() Method Last Updated : 11 Nov, 2024 Summarize Suggest changes Share 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 Advertise with us Next Article expandtabs() method in Python M manjeet_04 Follow 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. 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