Chrome will unload ad iframes that use an egregious amount of CPU or network bandwidth. An ad will be subject to unload if it has not received a user gesture and: * Used the main thread for more than 60 seconds total * Used the main thread for more than 15 seconds in any 30 second window (50% utilization over 30 seconds) * Used more than 4 megabytes of network bandwidth to load resources


A small fraction of ads on the web use an egregious amount of system resources. These poorly performant ads (whether intentional or not) harm the user’s browsing experience by making pages slow, draining device battery, and consuming mobile data (for those without unlimited plans).




Specification link

Proposal in a personal repository, no adoption from community

Status in Chromium


Browser Intervention (tracking bug)

Consensus & Standardization

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


Intent to Prototype url

Intent to Prototype thread


* Important * As this is a significant intervention, we intend to roll it out gradually throughout the month of September 2020 in Chrome 85.

Last updated on 2022-01-22