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.

AnimationEffect KeyframeEffect



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

Instance properties

Gets and sets the element, or originating element of the pseudo-element, being animated by this object. This may be null for animations that do not target a specific element or pseudo-element.


Gets and sets the selector of the pseudo-element being animated by this object. This may be null for animations that do not target a pseudo-element.

KeyframeEffect.iterationComposite Experimental

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.

Instance methods

This interface inherits some of its methods from its parent, AnimationEffect.


Returns the calculated, current timing values for this keyframe effect.


Returns the computed keyframes that make up this effect along with their computed keyframe offsets.


Returns the object associated with the animation containing all the animation's timing values.


Replaces the set of keyframes that make up this effect.


Updates the specified timing properties.


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:

const whiteRabbit = document.getElementById('rabbit');

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

const rabbitDownAnimation = new Animation(rabbitDownKeyframes, document.timeline);

// Play rabbit animation;


Web Animations
# the-keyframeeffect-interface

Browser compatibility

BCD tables only load in the browser

See also