Accept-CH
Accept-CH
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The Accept-CH
header may be set by a server to specify which client hints headers a client should include in subsequent requests.
Header type | Response header |
---|---|
Forbidden header name | no |
CORS-safelisted response header | no |
Note: Client hints are accessible only on secure origins (via TLS). Accept-CH
(and Accept-CH-Lifetime
) headers should be persisted for all secure requests to ensure client hints are sent reliably.
Syntax
Accept-CH: <list of client hints>
Examples
Accept-CH: Viewport-Width, Width Vary: Viewport-Width, Width
Note: Remember to vary the response based on the accepted client hints.
Specifications
Specification |
---|
HTTP Client Hints # section-3.1 |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
Accept-CH |
46
|
≤79
|
?
|
?
|
33
|
?
|
46
|
46
|
?
|
33
|
?
|
5.0
|
Content-DPR |
46
|
≤79
|
?
|
?
|
33
|
?
|
46
|
46
|
?
|
33
|
?
|
5.0
|
Device-Memory |
61
|
≤79
|
?
|
?
|
48
|
No
|
61
|
61
|
?
|
?
|
No
|
8.0
|
DPR |
46
|
≤79
|
?
|
?
|
33
|
?
|
46
|
46
|
?
|
33
|
?
|
5.0
|
Sec-CH-UA |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Sec-CH-UA-Arch |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Sec-CH-UA-Full-Version |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Sec-CH-UA-Mobile |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Sec-CH-UA-Model |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Sec-CH-UA-Platform |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Sec-CH-UA-Platform-Version |
89
|
89
|
No
|
No
|
75
|
No
|
89
|
89
|
No
|
63
|
No
|
No
|
Viewport-Width |
46
|
≤79
|
?
|
?
|
33
|
?
|
46
|
46
|
?
|
33
|
?
|
5.0
|
Width |
46
|
≤79
|
?
|
?
|
33
|
?
|
46
|
46
|
?
|
33
|
?
|
5.0
|
See also
© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-CH