Blob.size

The Blob interface's size property returns the size of the Blob or File in bytes.

Syntax

var sizeInBytes = blob.size

Value

The number of bytes of data contained within the Blob (or Blob-based object, such as a File).

Example

This example uses an <input> element of type file to ask the user for a group of files, then iterates over those files outputting their names and lengths in bytes.

// fileInput is a HTMLInputElement: <input type="file" multiple id="myfileinput">
var fileInput = document.getElementById("myfileinput");

// files is a FileList object (simliar to NodeList)
var files = fileInput.files;

for (var i = 0; i < files.length; i++) {
  console.log(files[i].name + " has a size of " + files[i].size + " Bytes");
}

Specifications

Specification Status Comment
File API
The definition of 'Blob.size' in that specification.
Working Draft Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
sizeChrome Full support 5Edge Full support 12Firefox Full support 4IE Full support 10Opera Full support 11Safari Full support 5.1WebView Android No support NoChrome Android Full support 18Firefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android No support No

Legend

Full support  
Full support
No support  
No support

See also