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

Syntax

strtoupper(string)

string – This parameter is required. It converts all characters of a string to uppercase.

Example

<?php
$str = 'Welcome to PHP Tutorials!';
echo strtoupper($str); // Output : WELCOME TO PHP TUTORIALS!
?>