html5 video change play back options with javascript code example

Example 1: how to set video speed html

/* play video twice as fast */
document.querySelector('video').defaultPlaybackRate = 2.0;
document.querySelector('video').play();

/* now play three times as fast just for the heck of it */
document.querySelector('video').playbackRate = 3.0;

Example 2: increase playback speed stack overflow

javascript:document.getElementsByClassName("video-stream html5-main-video")[0].playbackRate = 0.1;