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---
title: '@viewport'
slug: Web/CSS/@viewport
tags:
  - Adaptation
  - At-rule
  - CSS
  - Device
  - NeedsContent
  - NeedsTranslation
  - Reference
  - TopicStub
translation_of: Web/CSS/@viewport
---
<p>{{CSSRef}}</p>

<h2 id="Summary">Summary</h2>

<p>The<strong> <code>@viewport</code></strong> <a href="/en/CSS" title="CSS">CSS</a> <a href="/en/CSS/At-rule" title="en/CSS/At-rule">at-rule</a> contains a set of nested descriptors in a CSS block that is delimited by curly braces. These descriptors control viewport settings, primarily on mobile devices.</p>

<h2 id="Syntax">Syntax</h2>

<p>A <em>zoom factor</em> of <code>1.0</code> or <code>100%</code> corresponds to no zooming. Larger values zoom in. Smaller values zoom out.</p>

<h3 id="Descriptors">Descriptors</h3>

<p>Browsers are supposed to ignore unrecognized descriptors.</p>

<dl>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/min-width"><code>min-width</code></a></dt>
 <dd>Used in the determination of the width of the viewport when the document is first displayed.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/max-width"><code>max-width</code></a></dt>
 <dd>Used in the determination of the width of the viewport when the document is first displayed.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/width"><code>width</code></a></dt>
 <dd>A shorthand descriptor for setting both <code>min-width</code> and <code>max-width</code></dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/min-height"><code>min-height</code></a></dt>
 <dd>Used in the determination of the height of the viewport when the document is first displayed.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/max-height"><code>max-height</code></a></dt>
 <dd>Used in the determination of the height of the viewport when the document is first displayed.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/height"><code>height</code></a></dt>
 <dd>A shorthand descriptor for setting both <code>min-height</code> and <code>max-height</code></dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/zoom"><code>zoom</code></a></dt>
 <dd>Sets the initial zoom factor.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/min-zoom"><code>min-zoom</code></a></dt>
 <dd>Sets the minimum zoom factor.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/max-zoom"><code>max-zoom</code></a></dt>
 <dd>Sets the maximum zoom factor.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/user-zoom"><code>user-zoom</code></a></dt>
 <dd>Controls whether or not the user should be able to change the zoom factor.</dd>
 <dt><a href="/en-US/docs/Web/CSS/@viewport/orientation"><code>orientation</code></a></dt>
 <dd>Controls the document's orientation.</dd>
</dl>

<h3 id="Formal_syntax">Formal syntax</h3>

{{csssyntax}}

<h2 id="Examples">Examples</h2>

<pre class="eval" style="font-size: 14px;">@viewport {
  min-width: 640px;
  max-width: 800px;
}
@viewport {
  zoom: 0.75;
  min-zoom: 0.5;
  max-zoom: 0.9;
}
@viewport {
  orientation: landscape;
}</pre>

<h2 id="Specifications" name="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('CSS3 Device', '#the-atviewport-rule', '@viewport')}}</td>
   <td>{{Spec2('CSS3 Device')}}</td>
   <td>Initial definition</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility">Browser compatibility</h2>

{{Compat("css.at-rules.viewport")}}

<h2 id="See_also">See also</h2>

<ul>
 <li>{{HTMLElement("meta")}}, specifically <code>&lt;meta name="viewport"&gt;</code></li>
 <li><a href="/en-US/docs/Mobile/Viewport_meta_tag">Using the viewport meta tag to control layout on mobile browsers</a></li>
</ul>