HTML Guide for video
The controlslist attribute on the <video> element is experimental, and not yet valid in the current HTML5 standard, so you should use it with caution as it may not be supported by all browsers.
<video> elements accept a height attribute to specify the width in CSS pixels. This value can only be an integer, it should not contain units or %. If you need to specify a percentage width, you can do that with CSS.
Here’s an example of setting width and height on a video element.
<video controls width="640" height="480">
<source src="/media/cc0-videos/flower.webm" type="video/webm">
</video>
<video> elements accept a width attribute to specify the width in CSS pixels. This value can only be an integer, it should not contain units or %. If you need to specify a percentage width, you can do that with CSS.
Here’s an example of setting width and height on a video element.
<video controls width="640" height="480">
<source src="/media/cc0-videos/flower.webm" type="video/webm">
</video>