Window scrollX
Example 1
Scroll the content by 100 pixels, and alert the scrollX and scrollY:
 window.scrollBy(100, 100);
 alert(window.scrollX + window.scrollY);
Try it Yourself »
More examples below.
Definition and Usage
The scrollX property returns the pixels a 
document has scrolled from the upper left corner of the window.
The scrollX property is read-only.
Note
The scrollX property is equal to the
pageXOffset property.
For cross-browser compatibility, use window.pageXOffset instead of window.scrollX.
See Also:
Syntax
window.scrollX
or just:
scrollX
Return Value
| Type | Description | 
| A number | The number of pixels the document has scrolled from the upper left corner of the window. | 
More Examples
Create a sticky navigation bar:
// Get the navbar
const navbar = document.getElementById("navbar");
// Get the offset position of the navbar
const sticky = navbar.offsetTop;
// Add the sticky class to the navbar when you reach its scroll position. Remove the sticky class when you leave the scroll position.
function myFunction() {
  if (window.scrollY >= sticky) {
    navbar.classList.add("sticky")
  } 
  else {
    navbar.classList.remove("sticky");
  }
  }
 Try it Yourself »
Browser Support
window.scrollX is supported in all browsers:
| Chrome | IE | Edge | Firefox | Safari | Opera | 
| Yes | 9-11 | Yes | Yes | Yes | Yes | 
 
 
