Chrome has allegedly begun downloading a 4GB file, “weights.bin,” without user consent, which is necessary for running Gemini Nano, Google’s on-device large language model (LLM). This information was reported by computer scientist Alexander Hanff on his website, The Privacy Guy. Hanff confirmed the presence of the file in the macOS Library directory associated with Chrome.
According to Hanff, Chrome does not prompt users for permission before downloading the file, which supports AI-powered features like scam detection. Google stated that Gemini Nano has been available since 2024 and requires local storage to operate but will uninstall automatically if device resources are low. The company also mentioned that since February 2026, users have the option to disable and remove the model directly within Chrome settings.
Hanff noted discrepancies in file deployment, observing that the “weights.bin” file was absent on a second Mac and a coworker’s laptop. He documented that after updating to Chrome version 148.0.7778.97, the file appeared on his personal laptop. He also experienced the reappearance of the file after deletion, stating that on Windows installations, Chrome re-downloads the file unless specific settings are changed or Chrome is uninstalled.
Hanff emphasized that users could disable AI features through Chrome settings, although he suggested that many may not have noticed this option. He raised potential legal concerns about the download process, citing possible violations of European privacy laws like GDPR.
In terms of environmental impact, Hanff estimated that deploying the 4GB file to 500 million devices could generate approximately 30,000 tonnes of CO2e emissions, equivalent to the annual emissions of 6,500 cars. This figure reflects only the initial deployment costs and does not account for further energy consumption associated with ongoing use.
Google’s response, provided to Engadget, mentioned the lightweight nature of the Gemini Nano model and its purpose in enhancing security features without sending user data to the cloud. The company reiterated users’ ability to manage the model through settings in Chrome.
As of May 6, 2026, the article has been updated to include Google’s statement regarding the on-device AI tools, reinforcing the toggling option for users.
