Client Hints headers are a new approach developed by the Chrome/Chromium team to allow web browsers to identify themselves and their capabilities to the websites that you visit. Traditionally browser detection was done by a combination of User Agent Parsing and feature detection, however technology continues to evolve and Client Hints are starting to augment and maybe one day even replace the older approaches.

Client Hints offer a more structured approach for web browsing clients to let the web servers they visit know about their browser, version, platform and so on.

The Client Hints system used by some web browsers is still in the early days, but here’s a page which will tell you what (if any) Client Hints your web browser is sending to our server.

Not all web browsers support Client Hints yet, you can investigate web browsers that support Client Hints.

NameYour valueDefinitionHeader/Accept-CH value
User Agent“Chromium”;v=”112″, “Google Chrome”;v=”112″, “Not:A-Brand”;v=”99″The Agent (Browser) that’s making the requestSEC-CH-UA
User Agent Full version“112.0.5615.138”The full version of the user agent (Browser)SEC-CH-UA-FULL-VERSION
Platform“Windows”The platform of the deviceSEC-CH-UA-PLATFORM
Platform version“10.0.0”The full platform versionSEC-CH-UA-PLATFORM-VERSION
Architecture“x86”The CPU architecture of of the deviceSEC-CH-UA-ARCH
Model“”The model of the deviceSEC-CH-UA-MODEL
Mobile?0Is it a mobile device?SEC-CH-UA-MOBILE
Viewport Width1536The width of the primary screenVIEWPORT-WIDTH
Downlink2.65Megabits Per Second (mbps) – approximate speed of the user’s connectionDOWNLINK
Effective Connection Type4gBasic outline of the user’s connection typeECT
Round Trip Time250An estimate of the round trip time of the request (on the application layer)RTT
Device Memory8Roughly how many gigabytes of RAM the device hasDEVICE-MEMORY
Device Pixel Ratio1.25The ratio of pixelsDPR
Prefers color schemelightIf the user prefers light or dark modeSEC-CH-PREFERS-COLOR-SCHEME
Prefers Reduced Motionno-preferenceSEC-CH-PREFERS-REDUCED-MOTION

Client Hints detected with JavaScript

NameYour valueDefinitionBrowser property
Architecturex86The CPU architecture of the device you’re usingarchitecture
Bitness64The CPU architecture of your devicebitness
Brands StringChromium: 112. Google Chrome: 112. Not:A-Brand: 99.The Brand/Name of your browsernavigator.userAgentData.brands
ModelnullThe model number of your devicemodel
PlatformWindowsThe Platform (or Operating System) you’re usingplatform
Platform Version10.0.0The Platform (or Operating System) version numberplatformVersion
UA Full Version112.0.5615.138The full version number of your browseruaFullVersion

More Information

You can find more information about Client Hints at these links:

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