: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.

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.

• MDN Understanding WCAG, Guideline 3.3 explanations
• Understanding Success Criterion 3.3.2 | W3C Understanding WCAG 2.0

Specifications

Browser compatibility

See also

• Other validation-related pseudo-classes: :optional, :invalid, :valid
• Form data validation