---
title: Number.NaN
slug: Web/JavaScript/Reference/Global_Objects/Number/NaN
translation_of: Web/JavaScript/Reference/Global_Objects/Number/NaN
---
<div>{{JSRef("Global_Objects", "Number")}}</div>

<h2 id="Summary" name="Summary" style="margin-bottom: 20px; line-height: 30px;">概述</h2>

<p><code><strong>Number.NaN</strong></code> 表示“非数字”（Not-A-Number）。和 {{jsxref("Global_Objects/NaN", "NaN")}} 相同。</p>

<p>不必创建一个 {{jsxref("Global_Objects/Number", "Number")}} 实例来访问该属性，使用 <code>Number.NaN</code> 来访问该静态属性。</p>

<p>{{js_property_attributes(0,0,0)}}</p>

<h2 id="规范" style="margin-bottom: 20px; line-height: 30px;">规范</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('ES1')}}</td>
   <td>{{Spec2('ES1')}}</td>
   <td>Initial definition. Implemented in JavaScript 1.1.</td>
  </tr>
  <tr>
   <td>{{SpecName('ES5.1', '#sec-15.7.3.4', 'Number.NaN')}}</td>
   <td>{{Spec2('ES5.1')}}</td>
   <td> </td>
  </tr>
  <tr>
   <td>{{SpecName('ES6', '#sec-number.nan', 'Number.NaN')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td> </td>
  </tr>
  <tr>
   <td>{{SpecName('ESDraft', '#sec-number.nan', 'Number.NaN')}}</td>
   <td>{{Spec2('ESDraft')}}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性" style="margin-bottom: 20px; line-height: 30px;">浏览器兼容性</h2>

<p>{{ CompatibilityTable() }}</p>

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th style="line-height: 16px;">Feature</th>
   <th style="line-height: 16px;">Chrome</th>
   <th style="line-height: 16px;">Firefox (Gecko)</th>
   <th style="line-height: 16px;">Internet Explorer</th>
   <th style="line-height: 16px;">Opera</th>
   <th style="line-height: 16px;">Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th style="line-height: 16px;">Feature</th>
   <th style="line-height: 16px;">Android</th>
   <th style="line-height: 16px;">Chrome for Android</th>
   <th style="line-height: 16px;">Firefox Mobile (Gecko)</th>
   <th style="line-height: 16px;">IE Mobile</th>
   <th style="line-height: 16px;">Opera Mobile</th>
   <th style="line-height: 16px;">Safari Mobile</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>
  </tr>
 </tbody>
</table>
</div>

<h2 id="See_also" name="See_also" style="margin-bottom: 20px; line-height: 30px;">相关链接</h2>

<ul>
 <li>全局对象 {{jsxref("Global_Objects/NaN", "NaN")}}</li>
 <li>{{jsxref("Global_Objects/Number", "Number")}}</li>
</ul>