In all recent browser:
window.innerWidth // 1920
In Internet explorer 8
window.innerWidth // undefined
Without jQuery you can try this to get height and width
var myWidth = 0, myHeight = 0;
if (typeof (window.innerWidth) == 'number') { //Chrome
myWidth = window.innerWidth;
myHeight = window.innerHeight;
} else if (document.documentElement && (document.documentElement.clientWidth || document.documentElement.clientHeight)) {
myWidth = document.documentElement.clientWidth;
myHeight = document.documentElement.clientHeight;
} else if (document.body && (document.body.clientWidth || document.body.clientHeight)) { //IE9
myWidth = document.body.clientWidth;
myHeight = document.body.clientHeight;
}