This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The Animation
.currentTime
property of the Web Animations API returns and sets the current time value of the animation in milliseconds, whether running or paused.
If the animation lacks a timeline
, is inactive, or hasn't been played yet, currentTime
's return value is null
.
Syntax
var currentTime = Animation.currentTime; Animation.currentTime = newTime;
Value
A number representing the current time in milliseconds, or null
to deactivate the animation.
Examples
In the Drink Me/Eat Me game, Alice's height is animated so it can go from small to large or large to small. At the start of the game, her height is set between the two extremes by setting her animation's currentTime
to half her KeyframeEffect
's duration:
aliceChange.currentTime = aliceChange.effect.timing.duration / 2;
A more generic means of seeking to the 50% mark of an animation would be:
animation.currentTime = animation.effect.getComputedTiming().delay + animation.effect.getComputedTiming().activeDuration / 2;
Reduced time precision
To offer protection against timing attacks and fingerprinting, the precision of animation.currentTime
might get rounded depending on browser settings.
In Firefox, the privacy.reduceTimerPrecision
preference is enabled by default and defaults to 20us in Firefox 59; in 60 it will be 2ms.
// reduced time precision (2ms) in Firefox 60 animation.currentTime; // 23.404 // 24.192 // 25.514 // ... // reduced time precision with `privacy.resistFingerprinting` enabled animation.currentTime; // 49.8 // 50.6 // 51.7 // ...
In Firefox, you can also enabled privacy.resistFingerprinting
, the precision will be 100ms or the value of privacy.resistFingerprinting.reduceTimerPrecision.microseconds
, whichever is larger.
Specifications
Specification | Status | Comment |
---|---|---|
Web Animations The definition of 'currentTime' in that specification. |
Working Draft |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
currentTime | Chrome Full support 39 | Edge Full support ≤79 | Firefox
Full support
48
| IE No support No | Opera Full support 26 | Safari No support No | WebView Android Full support 39 | Chrome Android Full support 39 | Firefox Android
Full support
48
| Opera Android Full support 26 | Safari iOS No support No | Samsung Internet Android Full support 4.0 |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- User must explicitly enable this feature.
- User must explicitly enable this feature.
See also
Animation
for other methods and properties you can use to control web page animation.Animation.startTime
for the time an animation is scheduled to start.- Web Animations API