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:required

The :required CSS pseudo-class represents any <input>, <select>, or <textarea> element that has the required attribute set on it.

/* Selects any required <input> */
input:required {
  border: 1px dashed red;
}

This pseudo-class is useful for highlighting fields that must have valid data before a form can be submitted.

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

Syntax

:required

Examples

See :invalid for an example.

Specifications

Specification Status Comment
HTML Living Standard
The definition of ':required' in that specification.
Living Standard No change.
HTML5
The definition of ':required' in that specification.
Recommendation Defines the semantics of HTML and constraint validation.
Selectors Level 4
The definition of ':required' in that specification.
Working Draft No change.
CSS Basic User Interface Module Level 3
The definition of ':required' in that specification.
Proposed Recommendation Defines the pseudo-class, but not the associated semantics.

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 10 Yes 4 10 10 5
Feature Android webview Chrome for Android Edge mobile Firefox for Android Opera Android iOS Safari Samsung Internet
Basic support 4.4.4 ? Yes 4 10 5 ?

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/CSS/:required