XMLHttpRequest.getAllResponseHeaders()

The XMLHttpRequest.getAllResponseHeaders() method returns all the response headers, separated by CRLF, as a string, or null if no response has been received. If a network error happened, an empty string is returned.

Note: For multipart requests, this returns the headers from the current part of the request, not from the original channel.

Syntax

var headers = XMLHttpRequest.getAllResponseHeaders();

Parameters

None.

Return value

A ByteString representing all of the response's headers (except those whose field name is Set-Cookie or Set-Cookie2) separated by CRLF, or null if no response has been received. If a network error happened, an empty string is returned.

Example

var request = new XMLHttpRequest();
request.open("GET", "foo.txt", true);
request.send();
request.onreadystatechange = function() {
  if(this.readyState == this.HEADERS_RECEIVED) {
    console.log(request.getAllResponseHeaders());
  }
}

Specifications

Specification	Status	Comment
XMLHttpRequest The definition of 'getAllResponseHeaders()' in that specification.	Living Standard	WHATWG living standard

Feature	Chrome	Edge	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	1	(Yes)	1.0 (1.7 or earlier)^[1]	5^[2] 7	(Yes)	1.2

Feature	Android	Chrome for Android	Edge	Firefox Mobile (Gecko)	IE Mobile	Opera Mobile	Safari Mobile
Basic support	?	1.0	(Yes)	1.0 (1.0)	?	?	?

[1] Starting from Firefox 49, empty headers are returned as empty strings in case the preference network.http.keep_empty_response_headers_as_empty_string is set to true, defaulting to false. Before Firefox 49 empty headers had been ignored. Since Firefox 50 the preference defaults to true.

[2] This feature was implemented via ActiveXObject(). Internet Explorer implements the standard XMLHttpRequest since version 7.