Animation: currentTime property
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
.
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:
js
aliceChange.currentTime = aliceChange.effect.timing.duration / 2;
A more generic means of seeking to the 50% mark of an animation would be:
js
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 20 microseconds in Firefox 59; in 60 it will be 2 milliseconds.
js
// 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 |
---|
Web Animations # dom-animation-currenttime |
Browser compatibility
BCD tables only load in the browser
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