The Access-Control-Allow-Credentials response header indicates whether or not the response to the request can be exposed to the page. It can be exposed when the true value is returned; it can't in other cases.

Credentials are cookies, authorization headers or TLS client certificates.

When used as part of a response to a preflight request, this indicates whether or not the actual request can be made using credentials. Note that simple GET requests are not preflighted, and so if a request is made for a resource with credentials, if this header is not returned with the resource, the response is ignored by the browser and not returned to web content.

The Access-Control-Allow-Credentials header works in conjunction with the XMLHttpRequest.withCredentials property or with the credentials option in the Request() constructor of the Fetch API. Credentials must be set on both sides (the Access-Control-Allow-Credentials header and in the XHR or Fetch request) in order for the CORS request with credentials to succeed.

Header type Response header
Forbidden header name no


Access-Control-Allow-Credentials: true


The only valid value for this header is true (case-sensitive). If you don't need credentials, omit this header entirely (rather than setting its value to false).


Allow credentials:

Access-Control-Allow-Credentials: true

Using XHR with credentials:

var xhr = new XMLHttpRequest();'GET', '', true); 
xhr.withCredentials = true; 

Using Fetch with credentials:

fetch(url, {
  credentials: 'include'  


Specification Status Comment
The definition of 'Access-Control-Allow-Credentials' in that specification.
Living Standard Initial definition

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari Servo
Basic Support4123.510124?
Feature Android Chrome for Android Edge Mobile Firefox for Android IE Mobile Opera Mobile Safari Mobile
Basic Support2.1(Yes)(Yes)1.0(Yes)123.2

See also

Document Tags and Contributors

 Contributors to this page: teoli, alex-pollan, fscholz
 Last updated by: teoli,