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The :default CSS pseudo-class represents any form element that is the default among a group of related elements.

This selector may be used on the <button><input type="checkbox">, <input type="radio">, and <option> elements.

/* Selects any default <input> */
input:default {
  background-color: lime;

Grouped elements that permit multiple selections may also have multiple defaults, i.e., they may have multiple items initially selected. In this case, all defaults are represented using the :default pseudo-class. For example, you can style the default checkboxes among a group of checkboxes.





<input type="radio" name="season" id="spring">
<label for="spring">Spring</label>

<input type="radio" name="season" id="summer" checked>
<label for="summer">Summer</label>

<input type="radio" name="season" id="fall">
<label for="fall">Fall</label>

<input type="radio" name="season" id="winter">
<label for="winter">Winter</label>


input:default {
  box-shadow: 0 0 2px 1px coral;

input:default + label {
  color: coral;



Specification Status Comment
HTML Living Standard
The definition of ':default' in that specification.
Living Standard No change.
The definition of ':default' in that specification.
Recommendation Defines associated HTML semantics and constraint validation.
Selectors Level 4
The definition of ':default' in that specification.
Working Draft No change.
CSS Basic User Interface Module Level 3
The definition of ':default' in that specification.
Proposed Recommendation Initial definition, but without the associated semantics.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support10 ?4 No105
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support ? ? ?4105 ?

Document Tags and Contributors

 Last updated by: fscholz,