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


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

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



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


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

  to {
    transform: translateY(25px);

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



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

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support ? ? ? ? ?
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? ? ? ?

Document Tags and Contributors

 Contributors to this page: mfluehr, y0ssar1an, Sebastianz, kscarfone, cvrebert
 Last updated by: mfluehr,