---
title: <resolution>
slug: Web/CSS/resolution
tags:
  - CSS
  - 参考系
  - 布局
translation_of: Web/CSS/resolution
---
<div>{{CSSRef}}</div>

<div>分辨率：用于描述<a href="/en-US/docs/Web/CSS/Media_Queries">媒体查询</a>中的分辨率的&lt;resolution&gt; CSS<a href="/en-US/docs/Web/CSS/CSS_Types">数据类型</a>表示输出设备的像素密度。</div>

<p>在屏幕上，单位与CSS英寸，厘米或像素有关，而与物理值无关。</p>

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

<p>&lt;resolution&gt;数据类型由严格为正{{cssxref("&lt;number&gt;")}}组成，后跟下面列出的单位之一。与所有CSS维度一样，单位字面值与数字之间没有空格。</p>

<h3 id="单位">单位</h3>

<dl>
 <dt><a id="dpi" name="dpi"><code id="dpi">dpi</code></a></dt>
 <dd>表示<a href="https://en.wikipedia.org/wiki/Dots_per_inch">每英寸的点数</a>。屏幕通常每英寸包含72或96个点，但打印文档的dpi通常要大得多。 1英寸是2.54厘米，1dpi≈0.39dpcm。</dd>
 <dt><a id="dpcm" name="dpcm"><code id="dpcm">dpcm</code></a></dt>
 <dd><a href="https://en.wikipedia.org/wiki/Dots_per_inch">每厘米上的点数</a>。1英寸是2.54厘米, <code>1dpcm ≈ 2.54dpi</code>.</dd>
 <dt><a id="dppx" name="dppx"><code id="dppx">dppx</code></a></dt>
 <dd>表示每个<code><a href="/en-US/docs/Web/CSS/length#px">px</a></code>的点数。 由于CSS px的固定比率为1:96，因此1dppx相当于96dpi。 which corresponds to the default resolution of images displayed in CSS as defined by {{cssxref("image-resolution")}}.</dd>
 <dt><a id="x" name="x"><code>x</code></a></dt>
 <dd> <code>dppx</code> 的别名</dd>
</dl>

<div class="note">
<p><strong>Note:</strong> Although the number <code>0</code> is always the same regardless of unit, the unit may not be omitted. In other words, <code>0</code> is invalid and does not represent <code>0dpi</code>, <code>0dpcm</code>, or <code>0dppx</code>.</p>
</div>

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

<h3 id="Use_in_a_media_query">Use in a media query</h3>

<pre class="brush: css">@media print and (min-resolution: 300dpi) { ... }</pre>

<h3 id="Valid_resolutions">Valid resolutions</h3>

<pre>96dpi
50.82dpcm
3dppx
</pre>

<h3 id="Invalid_resolutions">Invalid resolutions</h3>

<pre class="example-bad">72 dpi     Spaces are not allowed between the number and the unit.
ten dpi    The number must use digits only.
0          The unit is required.
</pre>

<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('CSS4 Values', '#resolution', '&lt;resolution&gt;')}}</td>
   <td>{{Spec2('CSS4 Values')}}</td>
   <td>Adds the <code>x</code> unit.</td>
  </tr>
  <tr>
   <td>{{SpecName('CSS3 Values', '#resolution', '&lt;resolution&gt;')}}</td>
   <td>{{Spec2('CSS3 Values')}}</td>
   <td>Adds the <code>dppx</code> unit.</td>
  </tr>
  <tr>
   <td>{{SpecName('CSS3 Media Queries', '#resolution', '&lt;resolution&gt;')}}</td>
   <td>{{Spec2('CSS3 Media Queries')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

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

<div>


<p>{{Compat("css.types.resolution")}}</p>
</div>

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

<ul>
 <li><a href="/en-US/docs/Web/CSS/@media/resolution">resolution</a> media feature</li>
</ul>