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 iterations property of the Web Animations API the number of times the animation should repeat. It defaults to 1, and can also take a value of Infinity to make it loop infinitely. 

Note: Element.animate(), KeyframeEffectReadOnly.KeyframeEffectReadOnly(), and KeyframeEffect.KeyframeEffect() all accept an object of timing properties including iterations. The value of iterations corresponds directly to AnimationEffectTimingReadOnly.iterations in timing objects returned by AnimationEffectReadOnly, KeyframeEffectReadOnly, and KeyframeEffect.


// Set the animation to run twice
var timingProperties = {
  iterations: 2


A whole number or decimal greater than or equal to 0, or Infinity. Defaults to 0.


In the Forgotten Key example, Alice waves her arm up and down infinitely by passing Infinity as the value for her iterations property:

// Get Alice's arm, and wave it up and down
  { transform: 'rotate(10deg)' }, 
  { transform: 'rotate(-40deg)' }
], {
  easing: 'steps(2, end)',
  iterations: Infinity,
  direction: 'alternate',
  duration: 600


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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support (Yes) 48 (48) No support (Yes) 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

See also


© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.

animate() Animation AnimationEffectTimingProperties AnimationEffectTimingReadOnly.iterations API Experimental iterations KeyframeEffect() KeyframeEffectReadOnly() Property Reference waapi web animations api