---
title: File.size
slug: Web/API/File/size
translation_of: Web/API/File/size
---
<p>{{APIRef("File API") }}</p>

<h2 id="概述">概述</h2>

<p><span class="short_text" id="result_box" lang="zh-CN"><span>以字节为单位返回文件的大小。</span></span></p>

<h2 id="语法">语法</h2>

<pre>var size = <em>instanceOfFile</em>.size</pre>

<h2 id="值">值</h2>

<p>一个数</p>

<h2 id="规范"><span class="short_text" id="result_box" lang="zh-CN"><span>规范</span></span></h2>

<p><span class="short_text" id="result_box" lang="zh-CN"><span>不属于任何规范。</span></span></p>

<h2 id="另请参见"><span class="short_text" id="result_box" lang="zh-CN"><span class="alt-edited">另请参见</span></span></h2>

<ul>
 <li>{{domxref("Blob.size")}}</li>
</ul>

<p> </p>