javascript check if window resized
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>JavaScript Window Resize Event</title>
</head>
<body>
<div id="result"></div>
<script>
// Defining event listener function
function displayWindowSize(){
// Get width and height of the window excluding scrollbars
var w = document.documentElement.clientWidth;
var h = document.documentElement.clientHeight;
// Display result inside a div element
document.getElementById("result").innerHTML = "Width: " + w + ", " + "Height: " + h;
}
// Attaching the event listener function to window's resize event
window.addEventListener("resize", displayWindowSize);
// Calling the function for the first time
displayWindowSize();
</script>
<p><strong>Note:</strong> Please resize the browser window to see how it works.</p>
</body>
</html>