Accept-CH header

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The HTTP Accept-CH 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.

Header type	Response header
CORS-safelisted response header	No

Syntax

http

Accept-CH: <client-hints-headers>

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

Examples

undefined

Client hint response headers

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