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XMLHttpRequest.responseType

The XMLHttpRequest property responseType is an enumerated string value specifying the type of data contained in the response. It also lets the author change the response type. If an empty string is set as the value of responseType, the default value of "text" is used.

Syntax

var type = XMLHttpRequest.responseType;

XMLHttpRequest.responseType = type;

Value

A string taken from the XMLHttpRequestResponseType enum which specifies what type of data the response contains.

When setting responseType to a particular value, the author should make sure that the server is actually sending a response compatible with that format. If the server returns data that is not compatible with the responseType that was set, the value of response will be null.

The values supported by responseType are the following:

Value	Description
`""`	An empty `responseType` string is treated the same as `"text"`, the default type (therefore, as a `DOMString`.
`"arraybuffer"`	The `response` is a JavaScript `ArrayBuffer` containing binary data.
`"blob"`	The `response` is a `Blob` object containing the binary data.
`"document"`	The `response` is an HTML `Document` or XML `XMLDocument`, as appropriate based on the MIME type of the received data. See HTML in XMLHttpRequest to learn more about using XHR to fetch HTML content.
`"json"`	The `response` is a JavaScript object created by parsing the contents of received data as JSON.
`"text"`	The `response` is text in a `DOMString` object.
`"moz-chunked-arraybuffer"`	Similar to `"arraybuffer"`, but the data is received in a stream. When using this response type, the value in `response` is only available in the handler for the `progress` event, and only contains the data received since the last `progress` event, rather than the cumulative data received since the request was sent. Accessing `response` during a `progress` event returns the data received so far. Outside the `progress` event handler, the value of `response` is always `null`.
`"ms-stream"`	The `response` is part of a streaming download; this response type is only allowed for download requests, and is only supported by Internet Explorer.

Exceptions

InvalidAccessError: An attempt was made to change the value of responseType on anXMLHttpRequest which is in synchronous mode but not in a Worker. For additional details, see Synchronous XHR restrictions below.

Usage notes

Synchronous XHR restrictions

You cannot change the value of responseType in a synchronous XMLHttpRequest except when the request belongs to a Worker. This restriction is designed in part to help ensure that synchronous operations aren't used for large transactions that block the browser's main thread, thereby bogging down the user experience.

XMLHttpRequests are asynchronous by default; they are only placed in synchronous mode by passing false as the value of the optional async parameter when calling open().

Restrictions in Workers

Attempts to set the value of responseType to "document" are ignored in a Worker.

Specifications

Specification	Status	Comment
XMLHttpRequest	Living Standard	WHATWG living standard

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	31	12	6	10	18	7
`arraybuffer`	10	Yes	6	10	18	Yes
`blob`	19	Yes	6	10	12	Yes
`document`	18	Yes	11	10	No	6.1
`json`	31	No	10	No	17 17 12 — 16	6.1
`moz-blob`	No	No	12 — 58	No	No	No

	Mobile
	Android webview	Chrome for Android	Edge Mobile	Firefox for Android	Opera for Android	iOS Safari	Samsung Internet
Basic support	55	55	Yes	50	Yes	?	6.0
`arraybuffer`	Yes	Yes	Yes	50	Yes	?	Yes
`blob`	Yes	Yes	Yes	50	Yes	?	Yes
`document`	Yes	Yes	Yes	50	Yes	?	Yes
`json`	Yes	Yes	No	50	?	?	Yes
`moz-blob`	No	No	No	No	No	No	No