Preference-Applied header

The HTTP Preference-Applied header informs the client about which preferences from the Prefer request header were applied by the server.

The server indicates if a preference is applied to a response if it would otherwise be ambiguous for the client.

Header typeResponse header
Forbidden request headerNo
CORS-safelisted response headerNo

Syntax

http
Preference-Applied: <preference>

Examples

undefined

Server applies timezone preferences

The following request indicates that the client prefers events to be represented in a certain time zone:

http
GET /events HTTP/1.1
Host: example.com
Prefer: timezone=America/Los_Angeles

The server supports the preference and sends back the content with a Preference-Applied header:

http
HTTP/1.1 200 OK
Content-Type: application/json
Preference-Applied: timezone=America/Los_Angeles

[
  {"t":"2023-10-18T05:37:59.611-07:00"},
  {"t":"2023-10-18T07:37:59.611-07:00"},
  {"t":"2023-10-18T09:37:59.611-07:00"}
]

Specifications

See also