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AnimationPlaybackEvent: currentTime property - Web APIs | MDN

AnimationPlaybackEvent: currentTime property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2020.

The currentTime read-only property of the AnimationPlaybackEvent interface represents the current time of the animation that generated the event at the moment the event is queued. This will be unresolved if the animation was idle at the time the event was generated.

In this article

Value

A number representing the current time in milliseconds, or null.

Reduced time precision

To offer protection against timing attacks and fingerprinting, the precision of playbackEvent.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 playbackEvent.currentTime will always be a multiple of 0.002, or a multiple of 0.1 (or privacy.resistFingerprinting.reduceTimerPrecision.microseconds) with privacy.resistFingerprinting enabled.

js
// reduced time precision (2ms) in Firefox 60 playbackEvent.currentTime; // Might be: // 23.404 // 24.192 // 25.514 // … // reduced time precision with `privacy.resistFingerprinting` enabled playbackEvent.currentTime; // Might be: // 49.8 // 50.6 // 51.7 // …

Specifications

Specification
Web Animations
# dom-animationplaybackevent-currenttime

Browser compatibility

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See also