Accept-CH

{{HTTPSidebar}} {{securecontext_header}} 

The HTTP Accept-CH {{Glossary("response header")}}  may be set by a server to specify which client hint headers should be included by the client in subsequent requests. To ensure client hints are sent reliably, the Accept-CH header should be persisted for all secure requests.

Syntax

Accept-CH: <client-hints-headers>

// Client hint headers in a comma-separated list
Accept-CH: <ch-header-one>, <ch-header-two>

Examples

Client hint response headers

The following response headers indicate that the server accepts Viewport-Width and Width device client hints in subsequent requests. The {{HTTPHeader("Vary")}}  header indicates which values were used to vary the response based on the accepted client hints.

Accept-CH: Viewport-Width, Width
Vary: Viewport-Width, Width

Specifications

{{Specifications}} 

Browser compatibility

{{Compat}} 

See also

• {{HTTPHeader("Vary")}}