:optional

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

Try it

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

css

:optional {
  /* ... */
}

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.

Examples

The optional field has a purple border

HTML

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

css

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

.field {
  margin: 1px;
  padding: 1px;
}

input:optional {
  border-color: rebeccapurple;
  border-width: 3px;
}

Result

Specifications

Specification
HTML Standard # selector-optional
Selectors Level 4 # opt-pseudos

Browser compatibility

BCD tables only load in the browser