YouTube (or more accurately the HTML video element) can go as fast as your computer can handle, the UI just doesn't surface it. Currently I use this bookmarklet

YouTube (or more accurately the HTML video element) can go as fast as your computer can handle, the UI just doesn't surface it. Currently I use this bookmarklet: javascript:void(document.getElementsByTagName("video")[0].playbackRate = prompt()) On another computer I have a variant that just sets that to all the video tags, as that works better on some sites, but this catches most video sites. I could have sworn I had a browser limiting me to 4x at one point but I just cranked a YouTube video up to 8x on my Chrome-based browser without anything objecting. I'm not sure what the limit is, and it may depend on your computer.