Feature Detection in CSS with @supports

Published on May 5, 2016

A new at-rule in CSS, @supports, allows you to easily detect if a certain CSS feature is available or not in the visitor’s browser. This allows you to make use of these features only for supported browsers or define specific rules only for browsers without support, and have other browsers completely ignore them. @supports is a pure CSS way to replace a tool like Modernizr. @supports allows you to test for both the support of a feature and the non-support of a feature:

@supports (column-count: 3) {
  div { column-count: 3; }
}

Non-support

Here’s how you would test and apply specific rules when a feature is not supported:

@supports not (display: flex) {
  .sidebar { float: left; }
}

Chain multiple CSS features using and / or operators:

@supports (display: flex)
or (display: -webkit-box)
or (display: -webkit-flex)
or (display: -ms-flexbox) {
 .menu {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
 }
}

One big caveat

There’s one major caveat to @supports right now: @supports itself is not universally supported. It’s not supported in Internet Explorer at all, not even version 11, and is has only been supported in Safari for iOS since v9.2. See the @supports Can I Use page for more details.

Because of that, it might be more practical to continue using Modernizr for some time, until most IE users have switched over to Edge.

@supports also has an handy JavaScript API that can be used to detect for features in JS.

Thanks for learning with the DigitalOcean Community. Check out our offerings for compute, storage, networking, and managed databases.

Learn more about our products

About the author

Alligator

Author

See author profile

Alligator.io is a developer-focused resource that offers tutorials and insights on a wide range of modern front-end technologies, including Angular 2+, Vue.js, React, TypeScript, Ionic, and JavaScript.

See author profile

Category:

Tutorial

Tags:

CSS

While we believe that this content benefits our community, we have not yet thoroughly reviewed it. If you have any suggestions for improvements, please let us know by clicking the “report an issue“ button at the bottom of the tutorial.