GlossaryPlayback speed

Playback speed

Playback speed is a video player setting that changes how fast a video plays, such as 0.5x for slow motion or 2x for double speed. Good players keep audio pitch natural at higher speeds, so voices do not sound squeaky. Playback speed is supported by the HTML5 video element and by native players on iOS and Android.

Why it matters

Speed controls let learners review content faster and let viewers slow down complex steps. For course, training and long-form talk content, this keeps people watching instead of leaving, and it is an expected feature on most modern players.

How it works

  1. The player offers a menu of speeds, such as 0.5x, 1x, 1.5x and 2x.
  2. Choosing a speed multiplies the normal playback rate by that value.
  3. The browser or player keeps audio pitch natural at the new speed by default.
  4. The app may save the viewer's choice so the next video starts at the same speed.

Does playback speed affect watch time?

Yes. Watching at 2x halves the real time spent, even if the viewer sees the whole video. Many analytics tools report time actually spent, so a learner finishing a 20-minute lesson at 2x shows about 10 minutes. Track completion and playhead position alongside watch time to judge engagement fairly. For a learning platform, FastPix Video Data reports farthest playhead position next to watch time for every view, so a learner who finished at 2x still shows as finished.

How do I change video playback speed in HTML5?

Set the playbackRate property on the video element. A value of 1.0 is normal speed, 0.5 is half speed and 2.0 is double speed. Browsers keep pitch natural by default, and you can turn that off with preservesPitch. Very high or low rates may mute audio in some browsers.

Where it's used

Online learning platforms, corporate training teams and podcast-style video apps offer playback speed so learners can move faster through familiar material and slow down for detailed steps.

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