The :invalid CSS pseudo-class represents any <input> or <form> element whose content fails to validate according to the input's type setting. This allows you to easily have invalid fields adopt an appearance that helps the user identify and correct errors.

By default, Gecko does not apply a style to the :invalid pseudo-class. However it does apply a style (a red "glow" using the box-shadow property) to the :-moz-ui-invalid pseudo-class, which applies in a subset of cases for :invalid.

You can disable the glow using the following CSS, or completely override it to alter the appearance of invalid fields.

:invalid {
  box-shadow: none;

:-moz-submit-invalid {
  box-shadow: none;

:-moz-ui-invalid {


Radio buttons

If any of the radio buttons in a group (that is, with the same value for their name attribute) is required, the :invalid pseudo-class is applied to all of them if none of the buttons in the group are selected.


This example presents a simple form that colors elements green when they validate and red when they don't.

HTML Content

  <label>Enter a URL:</label>
  <input type="url" />
  <br />
  <br />
  <label>Enter an email address:</label>
  <input type="email" required/>

CSS Content

input:invalid {
  background-color: #ffdddd;

form:invalid {
  border: 5px solid #ffdddd;

input:valid {
  background-color: #ddffdd;

form:valid {
  border: 5px solid #ddffdd;
input:required {
  border-color: #800000;
  border-width: 3px;

input:required:invalid {
  border-color: #C00000;


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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (<input>) 10.0 4.0 (2) 10 10.0 5.0
Apply it to <form> ? 13 (13) ? ? ?
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? 4.0 (2) No support 10.0 5.0
Apply it to <form> ? 13.0 (13) ? ? ?

See also

Document Tags and Contributors

 Last updated by: Lemondoge,