PHP mb_strtolower() Function Last Updated : 28 Apr, 2025 Comments Improve Suggest changes Like Article Like Report The mb_strtolower() is a PHP inbuilt function that returns lowercase alphanumeric characters. Syntax: mb_strtolower(string $string, ?string $encoding = null): stringParameters: This function accepts 2 parameters: string: This parameter specifies the lowercase string.encoding: This parameter denotes the character encoding, & in case omitted or null, then the internal character encoding value will be utilized.Return value: This function converted the uppercase string into lowercase alphanumeric characters and then returns those characters. Example 1: The following code shows the working for the mb_strtolower() function. PHP <?php $str = "GEEKSFORGEEKS" ; $str2 = mb_strtolower($str); echo $str2; ?> Output: geeksforgeeks Example 2: The following code shows the working for the mb_strtolower() function. PHP <?php $str = "Dmmm" ; $str2 = mb_strtolower($str); echo $str2; ?> Output: dmmm Reference: https://www.php.net/manual/en/function.mb-strtolower.php Comment More infoAdvertise with us Next Article PHP mb_strtolower() Function N neeraj3304 Follow Improve Article Tags : PHP PHP-function PHP-Multibyte-String Similar Reads PHP mb_strstr() Function The mb_strstr() function is an inbuilt function in PHP that finds the first occurrence of a given string in the main string, i.e. it will search for the occurrence of the first needle in haystack, & id found then the portion of the haystack will be returned, otherwise return false. Syntax: mb_st 2 min read PHP mb_strlen() Function The mb_strlen() is an inbuilt PHP function that returns the string length in an integer. Syntax: mb_strlen($string, $encoding ): intParameters: This function accepts 2 parameters that are described below: $string: The string parameter whose lengths need to be determined. It is a required parameter.$ 1 min read PHP mb_strtoupper() Function The mb_strtoupper() function is an inbuilt function in PHP that helps to transform the multibyte string to uppercase. Syntax: mb_strtoupper(string $string, ?string $encoding = null): string Parameters: This function has two parameters: string: This parameter specifies the string that is to be made t 1 min read PHP mb_stristr() Function The mb_stristr() is an inbuilt function in PHP that is used to get the first occurrence of a string within another string. It will check case insensitivity. Syntax:mb_stristr( $haystack, $needle, $before_needle, $encoding = null ): string|falseParameters: This function accepts 4 parameters that are 2 min read PHP mb_strpos() Function The mb_strpos() function is an inbuilt function in PHP that finds the position of string occurrence in the string. Syntax: mb_strpos( $haystack, $needle, $offset, $encoding ): int|falseParameters: This function accepts 4 parameters that are described below: $haystack: This parameter is the main stri 2 min read Like