Client Hints enables user agents to provide device-specific preferences in the HTTP request headers. Accept-CH-Lifetime adds a client hint that allow origins to persist their opt-in policy for a specified period so they can receive client hints on main frame requests. Additionally, on the first page load, this feature provides hints for all subresources of the page. This is expected to be enabled by default in Chrome 67.




Working draft or equivalent

Status in Chromium


Enabled by default (tracking bug) in:

  • Chrome for desktop release 67
  • Chrome for Android release 67

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.

  • No signal
  • No signal
  • No signal
  • Positive


Search tags

client hints, blink, screen size, device memory, rtt, downlink, ect, effective type,

Last updated on 2021-03-12