我们的志愿者还没有将这篇文章翻译为 中文 (简体)加入我们帮助完成翻译!
您也可以阅读此文章的English (US)版。

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 KeyframeEffect interface of the Web Animations API lets us create sets of animatable properties and values, called keyframes. These can then be played using the Animation() constructor.


Returns a new KeyframeEffect object instance, and also allows you to clone an existing keyframe effect object instance.


This interface inherits some of its methods and properties from its parent, KeyframeEffectReadOnly, and its grandparent AnimationEffectReadOnly.

The AnimationEffectTimingReadOnly object associated with the animation containing all the animation's timing values.
Gets and sets the element or pseudo-element being animated by this object. This may be null for animations that do not target a specific element.

Future properties

The following options are currently not shipped anywhere, but will be added in the near future.

Gets and sets the iteration composite operation for resolving the property value changes of this keyframe effect.
Gets and sets the composite operation property for resolving the property value changes between this and other keyframe effects.


Returns the computed keyframes that make up this effect along with their computed keyframe offsets.
Replaces the set of keyframes that make up this effect.
Returns the calculated, current timing values for this keyframe effect.


In the Follow the White Rabbit example, the KeyframeEffect constructor is used to create a set of keyframes that dictate how the White Rabbit should animate down the hole:

 var rabbitDownKeyframes = new KeyframeEffect(
    whiteRabbit, // element to animate
      { transform: 'translateY(0%)' }, // keyframe 
      { transform: 'translateY(100%)' } // keyframe
    { duration: 3000, fill: 'forwards' } // keyframe options


Specification Status Comment
Web Animations
The definition of 'KeyframeEffect' in that specification.
Working Draft Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support (Yes) 48 (48)[1] No support No support No support
composite and iterationComposite options No support No support No support No support No support
Clone constructor (2nd type of constructor) (Yes) No support[2] No support No support No support
Feature Android Android Webview Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) 48.0 (48)[1] No support No support No support
composite and iterationComposite options No support No support No support No support No support No support No support
Clone constructor (2nd type) (Yes) (Yes) (Yes) No support[2] No support No support No support

[1] The Web Animations API is only enabled by default in Firefox Developer Edition and Nightly builds. You can enable it in beta and release builds by setting the preference dom.animations-api.core.enabled to true, and can disable it in any Firefox version by setting this preference to false.

[2] Only enabled in Firefox 52 Nightly and Dev edition. Turned off in Beta/release.

See also