The mb_strlen() is an inbuilt PHP function that returns the string length in an integer.

Syntax:

mb_strlen($string, $encoding ): int

Parameters: This function accepts 2 parameters that are described below:

• $string: The string parameter whose lengths need to be determined. It is a required parameter.
• $encoding: It is an optional parameter. This parameter described which type of encoding you are using in the string parameter. Here, the encoding parameter denotes the character encoding. In case if omitted or null, then the internal character encoding value will be utilized.

Return Values: The number of characters in the string that have the character encoding, will be returned by this function. It will count as 1 for the multi-byte character.

Example 1: The following program demonstrates the mb_strlen() function.

Output:

The length of the string is 5  

Example 2: The following program demonstrates the mb_strlen() function.

Output:

The length of the string is 13

Reference: https://www.php.net/manual/en/function.mb-strlen.php