Sec-CH-UA-Platform header

The HTTP Sec-CH-UA-Platform {{Glossary("request header")}} is a user agent client hint which provides the platform or operating system on which the user agent is running. For example: "Windows" or "Android".

Sec-CH-UA-Platform is a low entropy hint. Unless blocked by a user agent permission policy, it is sent by default (without the server opting in by sending {{HTTPHeader("Accept-CH")}}).

<table class="properties"> <tbody> <tr> <th scope="row">Header type</th> <td> {{Glossary("Request header")}}, <a href="/en-US/docs/Web/HTTP/Guides/Client_hints">Client hint</a> </td> </tr> <tr> <th scope="row">{{Glossary("Forbidden request header")}}</th> <td>Yes (<code>Sec-</code> prefix)</td> </tr> </tbody> </table>

Syntax

http

Sec-CH-UA-Platform: <platform>

Directives

<platform>
- : One of the following strings: "Android", "Chrome OS", "Chromium OS", "iOS", "Linux", "macOS", "Windows", or "Unknown".

Examples

Using Sec-CH-UA-Platform

As Sec-CH-UA-Platform is a low entropy hint it is typically sent in all requests. A browser running on a macOS computer might add the following header to all requests.

http

Sec-CH-UA-Platform: "macOS"

Syntax

Directives

Examples

Using Sec-CH-UA-Platform

Specifications

Browser compatibility

See also