This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

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.
Working Draft Initial definition

Browser compatibility

ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Chrome Full support 51Edge Full support 15Firefox Full support 55
Full support 55
No support 53 — 55
Disabled 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.
IE No support NoOpera Full support YesSafari ? WebView Android Full support 51Chrome Android Full support 51Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android Full support 5.0


Full support
Full support
No support
No support
Compatibility unknown
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
User must explicitly enable this feature.
User must explicitly enable this feature.