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.

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

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 20 µs in Firefox 59; in 60, it will be 2 ms.

// reduced time precision (2ms) in Firefox 60
playbackEvent.currentTime;
// 23.404
// 24.192
// 25.514
// …

// reduced time precision with `privacy.resistFingerprinting` enabled
playbackEvent.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.

• Web Animations API
• AnimationPlayBackEvent