Are you watching a YouTube video that goes too slow or too fast? It's easy to speed up (or slow down) the playback of any video on your YouTube site or YouTube mobile app. See below what you need to do.
How to change the playback speed of YouTube on the Web
To slow down or speed up a YouTube video to one Browser, visit YouTube.com and go to a YouTube video. Discover the player toolbar and do click in the "gear" icon located in the lower right corner of the video area.
In the menu that appears, click on "Playback speed".
In the "Playback speed" menu, you can select a speed anywhere between 0,25 times and 2 times the speed, including a customized price within this range. With "1" being the normal speed, any value less than 1 will slow down the video, while any value greater than 1 will speed up the video.
After that, click outside the menu to close and the next time you press the play button, the video will play at the speed you selected. If you need to change it back to normal, click the gear icon again, select "Playback speed" and select "1" from the list.
How to change YouTube playback speed in YouTube mobile app
If you want to slow down or speed up a YouTube video on your iPhone, iPad, or Android device, open the YouTube app first. When playing a video, Press on the screen once to display the tool bar and then press the button with the three dots in the upper right corner of the video frame.
In the menu that appears, select "Playback speed".
In the "Playback speed" list that appears, select speed you want. Remember that any value less than 1 slows down the video, while any number greater than 1 speeds up the video.
After that, close the menu and the video will continue at the selected speed. If you have to change back to normal speed, press the “ellipses” button again and change the speed to “1.”
Source of information: howtogeek.com