Web/CSS/ optional

From Get docs


The :optional CSS pseudo-class represents any <input>, <select>, or <textarea> element that does not have the required attribute set on it.

/* Selects any optional <input> */
input:optional {
  border: 1px dashed black;
}

This pseudo-class is useful for styling fields that are not required to submit a form.

Note: The :required pseudo-class selects required form fields.


Syntax

:optional

Examples

The optional field has a purple border

HTML

<form>
  <div class="field">
    <label for="url_input">Enter a URL:</label>
    <input type="url" id="url_input">
  </div>

  <div class="field">
    <label for="email_input">Enter an email address:</label>
    <input type="email" id="email_input" required>
  </div>
</form>

CSS

label {
  display: block;
  margin: 1px;  
  padding: 1px;
}

.field {
  margin: 1px;
  padding: 1px;
}
 
input:optional {
  border-color: rebeccapurple;
  border-width: 3px;
}

Result

Accessibility concerns

If a form contains optional <input>s, required inputs should be indicated using the required attribute. This will ensure that people navigating with the aid of assistive technology such as a screen reader will be able to understand which inputs need valid content to ensure a successful form submission.

Required inputs should also be indicated visually, using a treatment that does not rely solely on color to convey meaning. Typically, descriptive text and/or an icon are used.

Specifications

Specification Status Comment
HTML Living StandardThe definition of ':optional' in that specification. Living Standard No change.
HTML5The definition of ':optional' in that specification. Recommendation Defines the semantics of HTML and constraint validation.
Selectors Level 4The definition of ':optional' in that specification. Working Draft No change.

Browser compatibility

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
:optional Chrome

Full support 10

Edge

Full support 12

Firefox

Full support 4

IE

Full support 10

Opera

Full support 10

Safari

Full support 5

WebView Android

Full support 37

Chrome Android

Full support 18

Firefox Android

Full support 4

Opera Android

Full support 10.1

Safari iOS

Full support 5

Samsung Internet Android

Full support 1.0

Legend

Full support  
Full support


See also