Web/API/ValidityState/badInput

The read-only badInput property of a ValidityState object 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. Note: While this is unsupported in Internet Explorer, any non-numeric value will be dismissed from the field if it is a number input.

Example

<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.");
}

Specifications

Specification	Status	Comment
HTML Living StandardThe definition of 'ValidityState.badInput' in that specification.	Living Standard	Live Standard
HTML 5.1The definition of 'ValidityState.badInput' in that specification.	Recommendation	No change from the previous snapshot HTML5.
HTML5The definition of 'ValidityState.badInput' in that specification.	Recommendation	First snapshot of  HTML Living Standard containing this interface.

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
badInput	Chrome Full support 25	Edge Full support 14	Firefox Full support 29	IE No support No	Opera Full support 15	Safari Full support 11	WebView Android Full support 4.4	Chrome Android Full support Yes	Firefox Android Full support 64	Opera Android Full support 14	Safari iOS Full support 7	Samsung Internet Android Full support Yes

Legend

Full support  

Full support

No support  

No support

See also

• Guide: Constraint validation
• Tutorial: Form data validation

validityState.badInput by Mozilla Contributors is licensed under CC-BY-SA 2.5.