Web/API/Blob/Blob

The Blob() constructor returns a new Blob object. The content of the blob consists of the concatenation of the values given in the parameter array.

Syntax

var newBlob = new Blob(array, options);

Parameters

array: An Array of ArrayBuffer, ArrayBufferView, Blob, USVString objects, or a mix of any of such objects, that will be put inside the Blob. USVString objects are encoded as UTF-8.
options Optional: An optional object of type BlobPropertyBag which may specify any of the following properties:

type Optional The MIME type of the data that will be stored into the blob. The default value is the empty string, (""). endings Optional ' How to interpret newline characters (\n) within the contents, if the data is text. The default value, transparent, copies newline characters into the blob without changing them. To convert newlines to the host system's native convention, specify the value native.

Return value

A new Blob object containing the specified data.

Example

var aFileParts = ['<a id="a"><b id="b">hey!</b></a>']; // an array consisting of a single DOMString
var oMyBlob = new Blob(aFileParts, {type : 'text/html'}); // the blob

Specification

Specification	Status	Comment
File APIThe definition of 'Blob()' in that specification.	Working Draft	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`Blob()` constructor	Chrome Full support 20	Edge Full support 12	Firefox Full support 13 Notes' Full support 13 Notes' Notes' Before Firefox 16, the second parameter, when set to `null` or `undefined`, leads to an error instead of being handled as an empty dictionary.	IE Full support 10	Opera Full support 12	Safari Full support 8	WebView Android Full support 37	Chrome Android Full support 25	Firefox Android Full support 14 Notes' Full support 14 Notes' Notes' Before Firefox 16, the second parameter, when set to `null` or `undefined`, leads to an error instead of being handled as an empty dictionary.	Opera Android Full support 12	Safari iOS Full support 8	Samsung Internet Android Full support 1.5

Legend

Full support: Full support
See implementation notes.': See implementation notes.