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The read-only property ValidityState.badInput indicates if the user has provided input that the browser is unable to convert. For example, if you have a number input element whose content is a string.


<input type="number" id="age">
var input = document.getElementById("age");
if (input.validity.badInput) {
  console.log("Bad input detected…");
} else {
  console.log("Content of input ok.");


Specification Status Comment
WHATWG HTML Living Standard
The definition of 'ValidityState.badInput' in that specification.
Living Standard Live Standard
HTML 5.1
The definition of 'ValidityState.badInput' in that specification.
Recommendation No change from the previous snapshot HTML5.
The definition of 'ValidityState.badInput' in that specification.
Recommendation First snapshot of  WHATWG HTML Living Standard containing this interface.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support ? 29 (29) ? ? ?
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? 29.0 (29) ? ? ?

See also

Document Tags and Contributors

 Contributors to this page: tkrotoff, cvrebert, Jeremie, teoli
 Last updated by: tkrotoff,