Returns the number of pixels that the document has already been scrolled horizontally.


var x = window.scrollX;


  • x is the number of pixels that the document is currently scrolled from the left.


// If scrollX is greater than 400, reset scroll position to the top left of the document.
if (window.scrollX > 400) {


The pageXOffset property is an alias for the scrollX property:

window.pageXOffset == window.scrollX; // always true

For cross-browser compatibility, use window.pageXOffset instead of window.scrollX. Additionally, older versions of Internet Explorer (< 9) do not support either property and must be worked around by checking other non-standard properties. A fully compatible example:

var x = (window.pageXOffset !== undefined)
  ? window.pageXOffset
  : (document.documentElement || document.body.parentNode || document.body).scrollLeft;

var y = (window.pageYOffset !== undefined)
  ? window.pageYOffset
  : (document.documentElement || document.body.parentNode || document.body).scrollTop;


Specification Status Comment
CSS Object Model (CSSOM) View Module
The definition of 'window.scrollX' in that specification.
Working Draft  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Microsoft Edge Opera Safari (WebKit)
Basic support (Yes) (Yes) No support (Yes) (Yes) (Yes)
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support ? (Yes) ? ? ? ? ? (Yes)

See also


© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.