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---
title: Element.querySelector()
slug: Web/API/Element/querySelector
translation_of: Web/API/Element/querySelector
---
<div>{{APIRef("DOM")}}</div>
<p>Returns the first element that is a descendant of the element on which it is invoked that matches the specified group of selectors.</p>
<h2 id="Syntax" name="Syntax">Syntax</h2>
<pre class="syntaxbox"><var>element</var> = <em>baseElement</em>.querySelector(<em>selector</em>s);
</pre>
<h3 id="Parameters">Parameters</h3>
<dl>
<dt><code>selectors</code></dt>
<dd>A group of <a href="/en-US/docs/Web/Guide/CSS/Getting_Started/Selectors">selectors</a> to match the descendant elements of the {{domxref("Element")}} <code>baseElement</code> against; this must be valid CSS syntax, or a <code>SyntaxError</code> exception will occur. The first element found which matches this group of selectors is returned.</dd>
</dl>
<h3 id="Return_value">Return value</h3>
<p>The first descendant element of <code>baseElement</code> which matches the specified group of <code>selectors</code>. The entire hierarchy of elements is considered when matching, including those outside the set of elements including <code>baseElement</code> and its descendants; in other words, <code>selectors</code> is first applied to the whole document, not the <code>baseElement</code>, to generate an initial list of potential elements. The resulting elements are then examined to see if they are descendants of <code>baseElement</code>. The first match of those remaining elements is returned by the <code>querySelector()</code> method.</p>
<p>If no matches are found, the returned value is <code>null</code>.</p>
<h3 id="Exceptions">Exceptions</h3>
<dl>
<dt><code>SyntaxError</code></dt>
<dd>The specified <code>selectors</code> are invalid.</dd>
</dl>
<h2 id="Examples">Examples</h2>
<p>Let's consider a few examples.</p>
<h3 id="Find_a_specific_element_with_specific_values_of_an_attribute">Find a specific element with specific values of an attribute</h3>
<p>In this first example, the first {{HTMLElement("style")}} element which either has no type or has type "text/css" in the HTML document body is returned:</p>
<pre class="brush:js">var el = document.body.querySelector("style[type='text/css'], style:not([type])");
</pre>
<h3 id="The_entire_hierarchy_counts">The entire hierarchy counts</h3>
<p>The next example, below, demonstrates that the hierarchy of the entire document is considered when applying <code>selectors</code>, so that levels which are outside the specified <code>baseElement</code> are still considered when locating matches.</p>
<h4 id="HTML">HTML</h4>
<pre class="brush: html"><div>
<h5>Original content</h5>
<p>
inside paragraph
<span>inside span</span>
inside paragraph
</p>
</div>
<div>
<h5>Output</h5>
<div id="output"></div>
</div></pre>
<h4 id="JavaScript">JavaScript</h4>
<pre class="brush: js">var baseElement = document.querySelector("p");
document.getElementById("output").innerHTML =
(baseElement.querySelector("div span").innerHTML);</pre>
<h4 id="Result">Result</h4>
<p>The result looks like this:</p>
<p>{{ EmbedLiveSample('The_entire_hierarchy_counts', 600, 160) }}</p>
<p>Notice how the <code>"div span"</code> selector still matches the {{HTMLElement("span")}} element, even though the <code>baseElement</code> excludes the {{domxref("div")}} element which is part of the specified selector.</p>
<p>The :scope pseudo-class restores the expected behavior, only matching selectors on descendants of the baseElement.</p>
<h3 id="More_examples">More examples</h3>
<p>See {{domxref("Document.querySelector()")}} for additional examples of the proper format for the <code>selectors</code>.</p>
<h2 id="Specifications">Specifications</h2>
<table class="standard-table">
<thead>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
</thead>
<tbody>
<tr>
<td>{{SpecName('DOM4','#dom-parentnode-queryselectorallselectors','querySelectorAll()')}}</td>
<td>{{Spec2('DOM4')}}</td>
<td> </td>
</tr>
<tr>
<td>{{SpecName('Selectors API Level 2','#queryselectorall','querySelectorAll()')}}</td>
<td>{{Spec2('Selectors API Level 2')}}</td>
<td> </td>
</tr>
<tr>
<td>{{SpecName('Selectors API Level 1','#queryselectorall','querySelectorAll()')}}</td>
<td>{{Spec2('Selectors API Level 1')}}</td>
<td> </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>Edge</th>
<th>Firefox (Gecko)</th>
<th>Internet Explorer</th>
<th>Opera</th>
<th>Safari (WebKit)</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatChrome(1)}}</td>
<td>12</td>
<td>{{CompatGeckoDesktop(1.9.1)}}</td>
<td>9<sup>[1][2]</sup></td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</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>Firefox OS (Gecko)</th>
<th>IE Phone</th>
<th>Opera Mobile</th>
<th>Safari Mobile</th>
<th>Chrome for Android</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
</tr>
</tbody>
</table>
</div>
<p>[1] <code>querySelector()</code> is supported in IE8, but only for CSS 2.1 selectors.<br>
[2] in IE8 and iE9 document must be in HTML5 mode (HTML5 doctype declaration present)</p>
<h2 id="See_also">See also</h2>
<ul>
<li>{{domxref("element.querySelectorAll()")}}</li>
<li>{{domxref("document.querySelector()")}}</li>
<li>{{domxref("document.querySelectorAll()")}}</li>
<li><a href="/en-US/docs/Code_snippets/QuerySelector">Code snippets for querySelector</a></li>
</ul>
|
