String length property

property length indicates the number of characters in the string.

 
<!DOCTYPE html>
<html>
<head>
    <title>Example</title>
    <script type="text/javascript">
        var stringValue = "hello world"; 
        document.writeln(stringValue.length); //"11" 
       
    </script>
</head>
<body>
</body>
</html>

Click to view the demo