Document: scroll event

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2020.

The scroll event fires when the document view has been scrolled. To detect when scrolling has completed, see the scrollend event of Document. For element scrolling, see scroll event of Element.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

js
addEventListener("scroll", (event) => {});

onscroll = (event) => {};

Event type

A generic Event.

Examples

Scroll event throttling

Since scroll events can fire at a high rate, the event handler shouldn't execute computationally expensive operations such as DOM modifications. Instead, it is recommended to throttle the event using requestAnimationFrame(), setTimeout(), or a CustomEvent, as follows.

Note, however, that input events and animation frames are fired at about the same rate, and therefore the optimization below is often unnecessary. This example optimizes the scroll event for requestAnimationFrame.

js
let lastKnownScrollPosition = 0;
let ticking = false;

function doSomething(scrollPos) {
  // Do something with the scroll position
}

document.addEventListener("scroll", (event) => {
  lastKnownScrollPosition = window.scrollY;

  if (!ticking) {
    window.requestAnimationFrame(() => {
      doSomething(lastKnownScrollPosition);
      ticking = false;
    });

    ticking = true;
  }
});

Specifications

Specification
CSSOM View Module
# eventdef-document-scroll
HTML
# handler-onscroll

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
scroll event

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

See also