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---
title: DOMImplementation.hasFeature
slug: Web/API/DOMImplementation/hasFeature
translation_of: Web/API/DOMImplementation/hasFeature
---
<p>{{ApiRef("DOMImplementation")}}</p>
<p>The <strong><code>DOMImplementation.hasFeature()</code></strong> method returns a {{domxref("Boolean")}} flag indicating if a given feature is supported.</p>
<p>The different implementation fairly diverged in what kind of features was reported. The latest version of the spec settled to force this method to always return <code>true</code>, except for SVG features, where the functionnality was accurate and in use.</p>
<h2 id="Syntax">Syntax</h2>
<pre class="syntaxbox"><em>flag</em> = document.implementation.hasFeature(<em>feature</em>, <em>version</em>);</pre>
<h3 id="Parameters">Parameters</h3>
<dl>
 <dt>
  <em>feature</em></dt>
 <dd>
  Is a {{domxref("DOMString")}} representing the feature name.</dd>
 <dt>
  <em>version</em></dt>
 <dd>
  Is a {{domxref("DOMString")}} representing the version of the specification defining the feature.</dd>
</dl>
<h2 id="Specifications">Specifications</h2>
<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('DOM WHATWG', '#dom-domimplementation-hasfeature', 'DOMImplementation.hasFeature')}}</td>
   <td>{{Spec2('DOM WHATWG')}}</td>
   <td>Modified to always return <code>true</code> except for SVG features.</td>
  </tr>
  <tr>
   <td>{{SpecName('DOM3 Core', 'core.html#ID-5CED94D7', 'DOMImplementation.hasFeature')}}</td>
   <td>{{Spec2('DOM3 Core')}}</td>
   <td>No change from {{SpecName("DOM2 Core")}}</td>
  </tr>
  <tr>
   <td>{{SpecName('DOM2 Core', 'core.html#ID-5CED94D7', 'DOMImplementation.hasFeature')}}</td>
   <td>{{Spec2('DOM2 Core')}}</td>
   <td>No change from {{SpecName("DOM1")}}</td>
  </tr>
  <tr>
   <td>{{SpecName('DOM1', 'level-one-core.html#ID-5CED94D7', 'DOMImplementation.hasFeature')}}</td>
   <td>{{Spec2('DOM2 Core')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</h2>
<p>{{CompatibilityTable}}</p>
<div id="compat-desktop">
 <table class="compat-table">
  <tbody>
   <tr>
    <th>Feature</th>
    <th>Chrome</th>
    <th>Firefox (Gecko)</th>
    <th>Internet Explorer</th>
    <th>Opera</th>
    <th>Safari</th>
   </tr>
   <tr>
    <td>Basic support</td>
    <td>{{CompatVersionUnknown}}</td>
    <td>{{CompatGeckoDesktop("1.0")}}</td>
    <td>{{CompatVersionUnknown}}</td>
    <td>{{CompatVersionUnknown}}</td>
    <td>{{CompatVersionUnknown}}</td>
   </tr>
   <tr>
    <td>Always <code>true</code> for non-SVG features.</td>
    <td>{{CompatUnknown}}</td>
    <td>{{CompatGeckoDesktop("19.0")}}</td>
    <td>{{CompatUnknown}}</td>
    <td>{{CompatUnknown}}</td>
    <td>{{CompatUnknown}}</td>
   </tr>
  </tbody>
 </table>
</div>
<div id="compat-mobile">
 <table class="compat-table">
  <tbody>
   <tr>
    <th>Feature</th>
    <th>Android</th>
    <th>Firefox Mobile (Gecko)</th>
    <th>IE Mobile</th>
    <th>Opera Mobile</th>
    <th>Safari Mobile</th>
   </tr>
   <tr>
    <td>Basic support</td>
    <td>{{CompatVersionUnknown}}</td>
    <td>{{CompatGeckoMobile("1.0")}}</td>
    <td>{{CompatVersionUnknown}}</td>
    <td>{{CompatVersionUnknown}}</td>
    <td>{{CompatVersionUnknown}}</td>
   </tr>
   <tr>
    <td>Always <code>true</code> for non-SVG features.</td>
    <td>{{CompatUnknown}}</td>
    <td>{{CompatGeckoMobile("19.0")}}</td>
    <td>{{CompatUnknown}}</td>
    <td>{{CompatUnknown}}</td>
    <td>{{CompatUnknown}}</td>
   </tr>
  </tbody>
 </table>
</div>
<h2 id="See_also">See also</h2>
<ul>
 <li>The {{domxref("DOMImplementation")}} interface it belongs to.</li>
</ul>