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 (similar 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
File API
# dfn-size

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
size
5
12
4
10
11
5.1
≤37
18
No
No
No
1.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/Blob/size