Skip to content

Instantly share code, notes, and snippets.

Created March 16, 2012 19:25
Show Gist options
  • Save scottjehl/2051999 to your computer and use it in GitHub Desktop.
Save scottjehl/2051999 to your computer and use it in GitHub Desktop.
Reliably get viewport dimensions in JS
An experiment in getting accurate visible viewport dimensions across devices
(c) 2012 Scott Jehl.
MIT/GPLv2 Licence
function viewportSize(){
var test = document.createElement( "div" ); = "position: fixed;top: 0;left: 0;bottom: 0;right: 0;";
document.documentElement.insertBefore( test, document.documentElement.firstChild );
var dims = { width: test.offsetWidth, height: test.offsetHeight };
document.documentElement.removeChild( test );
return dims;
// Notes:
// relies on position:fixed support, but it should work in browsers that partially support position: fixed like iOS4 and such...
//sample usage: var viewportwidth = viewportSize().width;
Copy link


Copy link

It is now 7 years after you first posted this, and this weekend I found myself needing this functionality. I have been all over Stackoverflow and a whole pile of other sites, googling like crazy. The question has been asked a zillion times and there are ten zillion answers out there - and NONE of them work. At least not in Firefox 67.0.4. None, that is, except for yours. Thank you thank you thank you!

Copy link

mzibari commented Mar 14, 2020

This is FANTASTIC!!!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment