Web/CSS/@media/update-frequency

The update CSS media feature can be used to test how frequently (if at all) the output device is able to modify the appearance of content.

Syntax

The update feature is specified as a single keyword value chosen from the list below.

none

Once it has been rendered, the layout can no longer be updated. Example: documents printed on paper.

slow

The layout may change dynamically according to the usual rules of CSS, but the output device is not able to render or display changes quickly enough for them to be perceived as a smooth animation. Examples: e-book readers or severely underpowered devices.

fast

The layout may change dynamically according to the usual rules of CSS, and the output device is not unusually constrained in speed, so regularly-updating things like CSS Animations can be used. Example: computer screens.

Examples

HTML

<p>If this text animates for you, you are using a fast-updating device.</p>

CSS

@keyframes jiggle {
  from {
    transform: translateY(0);
  }

  to {
    transform: translateY(25px);
  }
}

@media (update: fast) {
  p {
    animation: 1s jiggle linear alternate infinite;
  }
}

Specifications

Specification	Status	Comment
Media Queries Level 4The definition of 'update' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
update media feature	Chrome No support No	Edge No support No	Firefox No support No	IE No support No	Opera No support No	Safari No support No	WebView Android No support No	Chrome Android No support No	Firefox Android No support No	Opera Android No support No	Safari iOS No support No	Samsung Internet Android No support No

Legend

No support  

No support

update by Mozilla Contributors is licensed under CC-BY-SA 2.5.