KeyframeEffect

Baseline Widely available *

This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2020.

* Some parts of this feature may have varying levels of support.

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

Constructor

KeyframeEffect()

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

Instance properties

KeyframeEffect.target

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.

KeyframeEffect.pseudoElement

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

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

KeyframeEffect.composite

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.

AnimationEffect.getComputedTiming()

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

KeyframeEffect.getKeyframes()

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

AnimationEffect.getTiming()

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

KeyframeEffect.setKeyframes()

Replaces the set of keyframes that make up this effect.

AnimationEffect.updateTiming()

Updates the specified timing properties.

Examples

In the following example, the KeyframeEffect constructor is used to create a set of keyframes that dictate how the rofl emoji should roll on the floor:

js
const emoji = document.querySelector("div"); // element to animate

const rollingKeyframes = new KeyframeEffect(
  emoji,
  [
    { transform: "translateX(0) rotate(0)" }, // keyframe
    { transform: "translateX(200px) rotate(1.3turn)" }, // keyframe
  ],
  {
    // keyframe options
    duration: 2000,
    direction: "alternate",
    easing: "ease-in-out",
    iterations: "Infinity",
  },
);

const rollingAnimation = new Animation(rollingKeyframes, document.timeline);

// play rofl animation
rollingAnimation.play();

html

body {
  box-shadow: 0 5px 5px pink;
}

div {
  width: fit-content;
  margin-left: calc(50% - 132px);
  font-size: 64px;
  user-select: none;
  margin-top: 1rem;
}