This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for the proper prefixes to use in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the spec changes.

The get() method of the Headers interface returns the first value of a given header from within a Headers object. If the requested header doesn't exist in the Headers object, the call returns null.

For security reasons, some headers can only be controller by the user agent. These headers include the forbidden header names and forbidden response header names.




The name of the HTTP header whose value you want to retrieve from the Headers object. If the given name is not the name of an HTTP header, this method throws a TypeError.


A ByteString representing the value of the header retrieved.


Creating an empty Headers object is simple:

var myHeaders = new Headers(); // Currently empty

You could add a header to this using Headers.append, then retrieve it using get():

myHeaders.append('Content-Type', 'image/jpeg');
myHeaders.get('Content-Type'); // Returns 'image/jpeg'

If the header has multiple values associated with it, only the first header value will be returned:

myHeaders.append('Accept-Encoding', 'deflate');
myHeaders.append('Accept-Encoding', 'gzip');
myHeaders.get('Accept-Encoding'); // Returns 'deflate' only, as it was the first value added

Note: Use Headers.getAll to return an array containing all values.


Specification Status Comment
The definition of 'get()' in that specification.
Living Standard  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 42
41 behind pref
39 (39)
34 behind pref
Not supported

28 behind pref

Not supported
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support Not supported Not supported Not supported Not supported Not supported Not supported Not supported

See also


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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.