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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.

Accessibility concerns

Mandatory <input>s should have the required attribute applied to them. 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 submission.

If the form also contains optional inputs, required inputs should 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 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.	Recommendation	Defines the pseudo-class, but not the associated semantics.

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	10	Yes	4	10	10	5