Web/API/DOMImplementation/hasFeature

DeprecatedThis feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The DOMImplementation.hasFeature() method returns a Boolean flag indicating if a given feature is supported. It is deprecated and modern browsers return true in all cases.

The different implementations fairly diverged in what kind of features were reported. The latest version of the spec settled to force this method to always return true, where the functionality was accurate and in use.

Syntax

const flag = document.implementation.hasFeature(feature, version);

Parameters

feature: A DOMString representing the feature name.
version: A DOMString representing the version of the specification defining the feature.

Specifications

Specification	Status	Comment
DOMThe definition of 'DOMImplementation.hasFeature' in that specification.	Living Standard	Modified to always return `true` except for SVG features.
Document Object Model (DOM) Level 3 Core SpecificationThe definition of 'DOMImplementation.hasFeature' in that specification.	Obsolete	No change from Document Object Model (DOM) Level 2 Core Specification
Document Object Model (DOM) Level 2 Core SpecificationThe definition of 'DOMImplementation.hasFeature' in that specification.	Obsolete	No change from Document Object Model (DOM) Level 1 Specification
Document Object Model (DOM) Level 1 SpecificationThe definition of 'DOMImplementation.hasFeature' in that specification.	Obsolete	Initial definition.

Browser compatibility

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
`hasFeature` Deprecated'	Chrome Full support Yes	Edge Full support 12	Firefox Full support Yes Notes' Full support Yes Notes' Notes' Since Firefox 19, `hasFeature()` mostly returns `true`.	IE Full support 6	Opera Full support Yes	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support Yes	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support Yes

Legend

Full support: Full support
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.
See implementation notes.': See implementation notes.