String toUpperCase()

toUpperCase() converts string to upper case.

 
<!DOCTYPE html>
<html>
<head>
    <title>Example</title>
    <script type="text/javascript">
    
        var stringValue = "hello world"; 
        document.writeln(stringValue.toUpperCase()); //"HELLO WORLD" 

       
    </script>
</head>
<body>
</body>
</html>

Click to view the demo