title: Why is the size of an uploaded file detected by the browser not the same as the size in the file system
body: <p>I want to prevent users from uploading files bigger than 1 Go in the <code>&lt;asp:FileUpload /&gt;</code>. The problem is that a file that show a size of 993 Mo (0.993 Go) in the file system is detected (using jQuery) with ...</p>
  
  <pre><code> $(":file").change(function () {
          alert($(this)[0].files[0].size);
  });
  </code></pre>
  
  <p>... as having a size of 1,017 Go in the web browser (both chrome and IE tell the same value). How is that and how can I have an accurate validation of the form if both size (browser one and file system one) are different ?</p>