How to Create a Video Background With CSS

If you want to engage first-time visitors on your website, you have about 10 to 20 seconds. To inject some life into your page content, you might want to try adding a background video with CSS.

Video backgrounds take up the entire width and height of the viewport (in other words, the visible page area) and add some visual flair to boost engagement. Over this video, you can place your featured page content — after all, it is just a background, and your content is most important.

Video backgrounds may seem like a fancy feature, but they’re actually easy to implement if you know some CSS. In this guide, we’ll show you how to add a simple fullscreen video background to your webpage, which you can tweak and adapt to your needs.

How to Create a Fullscreen Video Background With CSS

To show you how to create video backgrounds for your site, we'll share some code that you can copy to modify for your needs. We'll also see the code in action with some responsive video background CodePen modules.

Let’s start with our HTML. First, we’ll place a video on our page with the <video> tag and several attributes.

 
<video id="background-video" autoplay loop muted poster="https://assets.codepen.io/6093409/river.jpg">
<source src="https://assets.codepen.io/6093409/river.mp4" type="video/mp4">
</video>

All of these attributes are important for the background to work as intended, so let’s go through each one:

• The id attribute is for styling our video element with CSS. This is necessary to achieve the fullscreen background effect.
• The autoplay attribute starts the video automatically once the page loads.
• The loop attribute plays the video in an infinite loop.
• The muted attribute turns off sound for the video. Generally, you shouldn't play video sound on your page unless the user turns on sound. Doing so is an accessibility issue and can make for an unpleasant user experience.
• Finally, the poster image is shown on the screen as the video is loading, or in place of the video if it doesn’t load. We recommend making your poster image the first frame of your video for the smoothest look.

<video> tags usually include the controls attribute as well. However, we’ve left it out because we don’t want users pausing the video or skipping around.

Featured Resource

Free CSS Coding Templates

Fill out the form to get the free code snippets.

After our video element, let’s add some HTML filler content to see how text appears against our video background.

 
<h1>THIS IS A RIVER.</h1>
<h2>How majestic.</h2>

With the HTML done, let’s handle the CSS business. To turn our normal video into a background video, add the following CSS:

 
#background-video {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  z-index: -1;
}

Let’s go through each of these rules to understand what they do:

• height: 100vw (viewport width) and width: 100vh (viewport height) make the video extend to the full width and height of the viewport.
• object-fit: cover automatically sizes the background video to keep its original aspect ratio while filling the screen, clipping out edges of the video when necessary.
• position: fixed and the following left, right, top, and bottom position the video relative to the viewport and separates it from the rest of the page content. This keeps the video in place when the user scrolls, and allows other content to sit on top of it.
• z-index places the video background under accompanying content.

Next, we’ll add some styling for our other page content. For accessibility, make sure text placed over video provides ample color contrast with the background:

 
h1, h2 {
  color: white;
  font-family: Trebuchet MS;
  font-weight: bold;
  text-align: center;
}

h1 {
  font-size: 6rem;
  margin-top: 30vh;
}

h2 { font-size: 3rem; }

At this point, the video background will display nicely. But, we haven’t accounted for mobile devices yet. It’s usually a good idea to prevent auto-playing videos on mobile, since the data needed to play them is significant and users didn’t request to play the video in the first place.

Instead, we’ll add a media query that substitutes the video with our poster image on screens 750 pixels wide or smaller.

 
@media (max-width: 750px) {
    #background-video { display: none; }
    body {
      background: url("https://assets.codepen.io/6093409/river.jpg") no-repeat;
      background-size: cover;
    }
}

When we combine everything, we get a sleek video background that scales with the screen and displays an image on mobile devices. (Note: Click here to see the example with the video playing.)

See the Pen Video Background 1 by Christina Perricone (@hubspot) on CodePen.

If you need more help learning how to make this code work for your site, check out this CSS background YouTube video tutorial:

Add More Page Content

We’ve already put some headings on the page to see how content looks against a video background.

Still, your page will probably contain more content than a video background and some title text. So, let’s add a <main> section to our example that appears when the user scrolls down. This element will cover the video to bring the focus to your main content. (Note: Click here to see the example with the video playing.)

See the Pen Video Background 2 by Christina Perricone (@hubspot) on CodePen.

We’ve given our <main> element a background color to cover up the video, as well as a top margin in viewport height units. This way, the main content will appear as soon as the user starts scrolling.

A CSS Video Background to Engage Your Audience

Life is short, and nobody wants to waste their time on a run-of-the-mill webpage. With just a few lines of CSS, we’ve created a full-page video background template that you can customize for your audience.

Using a site's background for a video might not be the ideal choice for every website, and are usually a no-go on mobile websites due to their impact on mobile performance. However, if done well, video backgrounds can make quite an impact, and there’s no need to even push play.

Editor's note: This post was originally published in June 2021 and has been updated for comprehensiveness.