Edit in JSFiddle

<html>
<body>

<div id="screenwidth"></div>

<script>
var text = "";
text += "<p>InnerWidth: " + window.innerWidth + "</p>";
text += "<p>InnerHeight: " + window.innerHeight + "</p>";
text += "<p>OuterWidth: " + window.outerWidth + "</p>";
text += "<p>OuterHeight: " + window.outerHeight + "</p>";

document.getElementById("screenwidth").innerHTML = text;
</script>

</body>
</html>