Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
Sec-CH-UA-Arch user agent client hint request header provides the user-agent's underlying CPU architecture, such as ARM or x86.
This might be used by a server, for example, to select and offer the correct binary format of an executable for a user to download.
|Header type||Request header, Client hint|
|Forbidden header name||yes|
A string indicating the underlying platform architecture, such as:
"[arm64-v8a, armeabi-v7a, armeabi]".
A server requests the
Sec-CH-UA-Arch header by including the
Accept-CH in a response to some request from the client, using the name of the desired header as a token:
HTTP/1.1 200 OK Accept-CH: Sec-CH-UA-Arch
The client may choose to provide the hint, and add the
Sec-CH-UA-Arch header to subsequent requests.
For example, on a Windows X86 based computer, the client might add the header as shown:
GET /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-Arch: "x86"
Note above that the low entropy headers are added to the request even though not specified in the server response.
|User-Agent Client Hints |
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