Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The Accept-CH header is set by the server to specify which Client Hints headers a client should include in subsequent requests.
| Header type | Response header |
|---|---|
| Forbidden header name | ? |
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: DPR, Viewport-Width Accept-CH: Width Accept-CH-Lifetime: 86400 Vary: DPR, Viewport-Width, Width
Note: Remember to vary the response based on the accepted client hints.
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Accept-CH | Chrome Full support 46 | Edge Full support ≤79 | Firefox ? | IE ? | Opera Full support 33 | Safari ? | WebView Android Full support 46 | Chrome Android Full support 46 | Firefox Android ? | Opera Android Full support 33 | Safari iOS ? | Samsung Internet Android Full support 5.0 |
DPR | Chrome Full support 46 | Edge Full support ≤79 | Firefox ? | IE ? | Opera Full support 33 | Safari ? | WebView Android Full support 46 | Chrome Android Full support 46 | Firefox Android ? | Opera Android Full support 33 | Safari iOS ? | Samsung Internet Android Full support 5.0 |
Viewport-Width | Chrome Full support 46 | Edge Full support ≤79 | Firefox ? | IE ? | Opera Full support 33 | Safari ? | WebView Android Full support 46 | Chrome Android Full support 46 | Firefox Android ? | Opera Android Full support 33 | Safari iOS ? | Samsung Internet Android Full support 5.0 |
Width | Chrome Full support 46 | Edge Full support ≤79 | Firefox ? | IE ? | Opera Full support 33 | Safari ? | WebView Android Full support 46 | Chrome Android Full support 46 | Firefox Android ? | Opera Android Full support 33 | Safari iOS ? | Samsung Internet Android Full support 5.0 |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- Non-standard. Expect poor cross-browser support.
- Non-standard. Expect poor cross-browser support.