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

The composite property of a KeyframeEffectReadOnly or a KeyframeEffect resolves how an element's animation impacts its underlying property values. 

Note: For KeyframeEffect, this property is both a getter and a setter. For KeyframeEffectReadOnly, it is read-only.


// getting
var compositeEnumeration = keyframeEffect.composite;

// setting
keyframeEffect.composite = 'accumulate';


To understand these values, take the example of a keyframeEffect value of blur(2) working on an underlying property value of  blur(3).

The keyframeEffect overrides the underlying value it is combined with:  blur(2) replaces blur(3).
The keyframeEffect is added to the underlying value with which it is combined (aka additive):  blur(2) blur(3).
The keyframeEffect is accumulated on to the underlying value:  blur(5).


Specification Status Comment
Web Animations
The definition of 'keyframeEffectReadOnly.composite' in that specification.
Working Draft Editor's draft.

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support No support No support No support No support No support
Feature Android Android Webview Chrome for Android Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile
Basic support ? ? ? ? ? ? ? ?

See also

Document Tags and Contributors

 Contributors to this page: rachelnabors, chrisdavidmills, Nexii
 Last updated by: rachelnabors,