The strtolower() function is used to converts a string to lowercase. All other special characters or numeric characters in the string remains unchanged. This function is binary-safe.

Syntax:

strtolower(string)

string – This parameter is required. It specifies the string to convert.

Example:

<?php
$str = 'Welcome to PHP Tutorials!';
echo strtolower($str); // Output : welcome to php tutorials!
?>