demo · v144

High-entropy Policy Simulator

Toggle the policy directives. The page renders the Permissions-Policy header your server would send and a simulated outcome for each call to navigator.userAgentData.getHighEntropyValues(). The right panel makes the actual call and compares.

policy for ch-ua-high-entropy-values:

simulated outcome


      

this page's actual UA-CH call

navigator.userAgentData: checking…


      

the API

Permissions-Policy: ch-ua-high-entropy-values=(self)
# Top-level controls who can fetch model, platformVersion, fullVersionList, etc.
const data = await navigator.userAgentData.getHighEntropyValues([
  'model','platformVersion','fullVersionList','bitness','wow64'
]);

see also