Google has confirmed that its Chrome browser may automatically download several gigabytes of on-device artificial intelligence (AI) models to users’ computers in order to support a growing number of AI-powered features integrated into the browser.
The issue drew attention after users and researchers reported discovering a large file, known as “weights.bin”, stored inside the “OptGuideOnDeviceModel” folder on their devices. The file, estimated to be around 4 GB in size, appeared to download in the background without a clear notification, warning, or consent prompt.
Some users also reported that deleting the file did not permanently remove it, as Chrome could download it again automatically unless specific browser settings or enterprise policies were manually disabled.
In a support page published on the Chrome Help Centre, Google said the browser uses on-device generative AI models “to provide an enhanced browser experience” and to ensure AI-powered tools remain ready for use without relying entirely on cloud processing.
According to the company, these models support features such as writing assistance, scam detection, webpage summarisation, and tab organisation.
Google stated that Chrome may download these AI models “in the background” so that compatible features can function immediately when needed.
Some users noted that many people were unaware the downloads were taking place, particularly because the files could consume significant storage space on laptops and desktop computers. Others questioned why Chrome did not provide clearer warnings before initiating downloads of several gigabytes of data.
In the Chrome Help Centre documentation, Google explained how users can disable on-device AI features through Chrome’s settings menu, but the company did not directly address why the downloads were not more prominently disclosed during installation or updates.
Google said users can manage the feature by navigating to Chrome’s system settings and turning “On-device AI” on or off. Re-enabling the feature may trigger the browser to download the AI models again. The company also noted that deleting the AI models would disable only the features dependent on them, while other AI tools that do not rely on local models could continue functioning.
