files/en-us/web/http/reference/headers/sec-ch-ua-platform-version/index.md
{{SeeCompatTable}}{{SecureContext_Header}}
The HTTP Sec-CH-UA-Platform-Version {{Glossary("request header")}} is a user agent client hint which provides the version of the operating system on which the user agent is running.
Sec-CH-UA-Platform-Version: <version>
<version>
"11.0.0".
The version string on Linux is always empty.A server requests the Sec-CH-UA-Platform-Version header by including the {{HTTPHeader("Accept-CH")}} in a response to any request from the client, using the name of the desired header as a token:
HTTP/1.1 200 OK
Accept-CH: Sec-CH-UA-Platform-Version
The client may choose to provide the hint, and add the Sec-CH-UA-Platform-Version header to subsequent requests.
For example, the following request headers might be sent from a browser running on Windows 10.
GET /my/page HTTP/1.1
Host: example.site
Sec-CH-UA: " Not A;Brand";v="99", "Chromium";v="96", "Google Chrome";v="96"
Sec-CH-UA-Mobile: ?0
Sec-CH-UA-Platform: "Windows"
Sec-CH-UA-Platform-Version: "10.0.0"
{{Specifications}}
{{Compat}}