Animation: currentTime property

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 2ms. You can also enable privacy.resistFingerprinting, in which case the precision will be 100ms or the value of privacy.resistFingerprinting.reduceTimerPrecision.microseconds, whichever is larger.

For example, with reduced time precision, the result of animation.currentTime will always be a multiple of 0.002, or a multiple of 0.1 (or privacy.resistFingerprinting.reduceTimerPrecision.microseconds) with privacy.resistFingerprinting enabled.

// reduced time precision (2ms) in Firefox 60
animation.currentTime;
// Might be:
// 23.404
// 24.192
// 25.514
// …

// reduced time precision with `privacy.resistFingerprinting` enabled
animation.currentTime;
// Might be:
// 49.8
// 50.6
// 51.7
// …

Specifications

Browser compatibility

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