Automatic height when embedding a YouTube video?

Issue

i've embed a YouTube video on my website but the trouble is that i need the height to automatically adjust based on the width and the aspect ratio of the video. So if my width is 1280, my height should be 720 if the video is 16:9. I've tried using 'VW' and 'VH' units but these don't seem to work with an iframe. My width is already set proportionally.

My code is below:

<iframe style="margin-right: 1%; margin-left: 1%;" width="98%" height="" src="https://www.youtube.com/embed/HwzQbfde-kE" frameborder="0"></iframe>

Solution

This article contains a good answer, copied below.

CSS:

.video-container {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 */
  height: 0;
}
.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

Example Html

<div class="video-container">
    <iframe width="560" height="315" src="https://www.youtube.com/embed/_TyJeKKQh-s?controls=0" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
</div>

How this works: The container element is given a zero height and a percentage bottom padding. The percentage bottom padding is a percentage of the container width, so that gives it a fixed aspect ratio. But in order to get the iframe to show up inside the zero-height container, you need to make the container relative and the iframe absolute, positioned inside the div.

See a live example.

---

EDIT: If you need to use percentage width other than 100%, multiply the ratio by the width multiplying factor. See the example below:

.video-container {
  position: relative;
  padding-bottom: calc(56.25% * 0.75); /* 16:9 */
  width: 75%;
  height: 0;
}

Answered By - MD Ashik