Tryit Editor v1.8

Source Code:
<!DOCTYPE html> <html> <head> <script> function myFunction() { var w=window.outerWidth; var h=window.outerHeight; var txt="Window size: width=" + w + ", height=" + h; document.getElementById("demo").innerHTML=txt; } </script> </head> <body onresize="myFunction()"> <p>Try to resize the browser window.</p> <p id="demo"> </p> <p>Note: this example will not work properly in IE8 and earlier. IE8 and earlier do not support the outerWidth/outerHeight propery of the window object.</p> </body> </html>
Result:
W3Schools.com - Try it yourself