window.scrollY

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 when using relative scroll functions such as window.scrollBy, window.scrollByLines, or 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

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

Browser compatibility

See also

• window.scrollX