MDN wants to learn about developers like you:


This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The IntersectionObserverEntry interface's read-only boundingClientRect property returns a DOMRectReadOnly which in essence describes a rectangle describing the smallest rectangle that contains the entire target element.


var boundsRect = IntersectionObserverEntry.boundingClientRect;


A DOMRectReadOnly which describes the smallest rectangle that contains every part of the target element whose intersection change is being described. This value is obtained using the same algorithm as Element.getBoundingClientRect(), so refer to that article for details on precisely what is done to obtain this rectangle and what is and is not included within its bounds.

In the general case, however, it's safe to simply think of this as the bounds rectangle of the target element.


Specification Status Comment
Intersection Observer
The definition of 'IntersectionObserverEntry.boundingClientRect' in that specification.
Editor's Draft Initial definition

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support51

53 — 551


FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support5151(Yes)?(No)??

1. From version 53 until version 55 (exclusive): this feature is behind the dom.IntersectionObserver.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

Document Tags and Contributors

 Contributors to this page: fscholz, Sheppy
 Last updated by: fscholz,