DOMTokenList: supports() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2018.

The supports() method of the DOMTokenList interface returns true if a given token is in the associated attribute's supported tokens. This method is intended to support feature detection.

Syntax

js
supports(token)

Parameters

token

A string containing the token to query for.

Return value

A boolean value indicating whether the token was found.

Example

js
const iframe = document.getElementById("display");

if (iframe.sandbox.supports("an-upcoming-feature")) {
  // support code for mystery future feature
} else {
  // fallback code
}

if (iframe.sandbox.supports("allow-scripts")) {
  // instruct frame to run JavaScript
  //
  // (NOTE: This feature is well-supported; this is just an example!)
  //
}

Specifications

Specification
DOM
# ref-for-dom-domtokenlist-supports①

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
supports
Chrome – Full support
Chrome 49 (Release date: 2016-03-02)
footnote Full support
Edge – Full support
Edge 17 (Release date: 2018-04-30)
footnote Full support
Firefox – Full support
Firefox 49 (Release date: 2016-09-20)
footnote Full support
Opera – Full support
Opera 36 (Release date: 2016-03-15)
footnote Full support
Safari – Full support
Safari 10.1 (Release date: 2017-03-27)
footnote Full support
Chrome Android – Full support
Chrome Android 49 (Release date: 2016-03-09)
footnote Full support
Firefox for Android – Full support
Firefox for Android 49 (Release date: 2016-09-20)
footnote Full support
Opera Android – Full support
Opera Android 36 (Release date: 2016-03-31)
footnote Full support
Safari on iOS – Full support
Safari on iOS 10.3 (Release date: 2017-03-27)
footnote Full support
Samsung Internet – Full support
Samsung Internet 5 (Release date: 2016-12-15)
footnote Full support
WebView Android – Full support
WebView Android 49 (Release date: 2016-03-09)
footnote Full support
WebView on iOS – Full support
WebView on iOS 10.3 (Release date: 2017-03-27)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support