Google Chrome downloaded 4GB AI model

Google Chrome users have been reporting unexplained storage use after the browser downloaded a large on-device AI model tied to Google’s built-in AI features. ICO Optics published a guide on May 24 showing Mac file locations where users may find the model and how to remove it if they do not want it stored locally. Google’s own Chrome developer documentation says the browser manages Gemini Nano downloads automatically and that the model can be downloaded when built-in AI APIs are invoked. The model at the center of the reports is Gemini Nano, Google’s on-device foundation model for Chrome. Google says Chrome’s built-in AI system provides and manages foundation and expert models in the browser, including Gemini Nano, and describes model downloads, updates and purges as background processes handled by Chrome. ### Where is the 4GB file supposed to come from? Google’s documentation says Gemini Nano is downloaded “on demand” so Chrome can fetch the version that matches a user’s hardware. (ico-optics.org) The company says the initial model download is triggered by the first call to a `*.create` function for a built-in AI API that depends on Gemini Nano, such as the summarizer API. Google also says the exact model size can vary as the browser updates it. (developer.chrome.com) Chrome’s developer pages also say the model is intended for local use. Google says no data is sent to Google or third parties when the model is used, and that the browser can remove the model if available storage drops below 10 GB after download. ### Where can Mac users look for it? ICO Optics said Mac users can check under `~/Library/Application Support/Google/Chrome/Default` for large model-related files. (developer.chrome.com) Other reporting on the issue has pointed to Chrome directories containing model storage such as `OptGuideOnDeviceModel`, which has been described as holding several gigabytes of Gemini Nano weights. Google also gives users a browser-level way to inspect what is installed. (developer.chrome.com) Chrome’s documentation says users can determine the current model size by visiting `chrome://on-device-internals`, which exposes on-device model information inside the browser. ### Is Google saying this was a secret download? Google’s public developer documentation does not describe the download as secret, but it does say model management happens automatically in the background. (ico-optics.org) ICO Optics, Malwarebytes and other outlets characterized the process as silent because users said they were not separately prompted before the storage was used. A Google support page for enterprise users also shows the company is expanding Gemini in Chrome across supported devices and regions, adding to the set of AI features that can rely on local model support. (developer.chrome.com) Google said this month that it was introducing major Gemini in Chrome updates for macOS, Windows and Chromebook Plus devices. ### Can users remove it, and will it come back? Google’s model-management documentation includes a section on model deletion, indicating Chrome can purge models under certain conditions. (developer.chrome.com) Third-party reports, including Malwarebytes and TechSpot, said some users found that deleting model folders did not always end the issue because Chrome could download the files again when the related features were triggered. (support.google.com) ICO Optics advised users who want to keep storage use in check to inspect the Chrome directories it identified and monitor disk usage after removal. Google’s own documentation points users to `chrome://on-device-internals` for the current model footprint and says the browser continues to manage downloads and updates automatically as built-in AI features are used. (ico-optics.org) (developer.chrome.com)