{{APIRef}}
Summary
Returns the number of pixels that the document has already been scrolled vertically.
Syntax
var y = window.scrollY;
y
is the number of pixels that the document is currently scrolled from the top.
Example
// make sure and go down to the second page if (window.scrollY) { window.scroll(0, 0); // reset the scroll position to the top left of the document. } window.scrollByPages(1);
Notes
Use this property to check that the document hasn't already been scrolled some if you are using relative scroll functions such as {{domxref("window.scrollBy")}}, {{domxref("window.scrollByLines")}}, or {{domxref("window.scrollByPages")}}.
The pageYOffset
property is an alias for the scrollY
property:
window.pageYOffset == window.scrollY; // always true
For cross-browser compatibility, use window.pageYOffset
instead of window.scrollY
. 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 supportPageOffset = window.pageXOffset !== undefined; var isCSS1Compat = ((document.compatMode || "") === "CSS1Compat"); var x = supportPageOffset ? window.pageXOffset : isCSS1Compat ? document.documentElement.scrollLeft : document.body.scrollLeft; var y = supportPageOffset ? window.pageYOffset : isCSS1Compat ? document.documentElement.scrollTop : document.body.scrollTop;
Specification
- CSSOM View Module: window.scrollY (Editor's Draft)
See also
- {{domxref("window.scrollX")}}