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

The IntersectionObserverEntry interface's read-only rootBounds property is a DOMRectReadOnly corresponding to the target's root intersection rectangle, offset by the IntersectionObserver.rootMargin if one is specified.


var rootBounds = IntersectionObserverEntry.rootBounds;


A DOMRectReadOnly which describes the root intersection rectangle. For roots which are the Document's viewport, this rectangle is the bounds rectangle of the entire document. Otherwise, it's the bounds of the root element.

This rectangle is offset by the values in IntersectionObserver.rootMargin.


Specification Status Comment
Intersection Observer
The definition of 'IntersectionObserverEntry.rootBounds' in that specification.
Working Draft Initial definition

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support5115


53 — 551

No ? ?
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5151 Yes ? ? ? ?

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,