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 setKeyframes() method of the KeyframeEffect interface replaces the keyframes that make up the affected KeyframeEffect with a new set of keyframes.




A keyframe object or null. If set to null, the keyframes are replaced with a sequence of empty keyframes.

There are two different ways to format keyframes:

  1. An object containing key-value pairs consisting of the property to animate and an array of values to iterate over.

      opacity: [ 0, 1 ],          // [ from, to ]
      color:   [ "#fff", "#000" ] // [ from, to ]
    }, 2000);
  2. An array of objects (keyframes) consisting of properties and values to iterate over. This is the canonical format returned by the getKeyframes() method.

      { // from
        opacity: 0,
        color: "#fff"
      { // to
        opacity: 1,
     ​   color: "#000"
    ], 2000);

    With this latter form it is also possible to specify offsets for each keyframe by providing an offset value.

    element.animate([ { opacity: 1 },
                      { opacity: 0.1, offset: 0.7 },
                      { opacity: 0 } ],

    Note: offset values, if provided, must be between 0.0 and 1.0 and arranged in ascending order.

    Furthermore, using this form it is also possible to specify easing to apply between keyframes by providing an easing value as illustrated below.

    element.animate([ { opacity: 1, easing: 'ease-out' },
                      { opacity: 0.1, easing: 'ease-in' },
                      { opacity: 0 } ],

    In this example, the specified easing only applies from the keyframe where it is specified until the next keyframe. Any easing value specified on the options argument, however, applies across a single iteration of the animation — for the entire duration.

Return value



Exception Explanation
TypeError One or more of the frames were not of the correct type of object, the keyframes were not loosely sorted by offset, or a keyframe existed with an offset of less than 0 or more than 1.

Note: If the keyframes cannot be processed or are malformed, the KeyframeEffect's keyframes are not modified.


// passing an array of keyframe objects
  { color: 'blue' },
    { color: 'green', left: '10px' }

// passing an object with arrays for values
    color: ['blue', 'green'],
    left: [ '0', '10px']

// passing a single-member object
    color: 'blue'


Specification Status Comment
Web Animations
The definition of 'KeyframeEffect.setKeyframes()' in that specification.
Working Draft Editor's draft.

Browser compatibility

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 No support No support No support No support No support No support No support No support


See also


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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.