Chrome Silently Installs 4 GB Gemini Nano AI Model and Re‑Downloads It After Deletion

Context Chrome includes Gemini Nano, a lightweight version of Google’s large language model, to power on‑device features such as scam detection and developer APIs. The model resides in a folder named OptGuideOnDeviceModel, with the bulk of its size in a file called weights.bin that contains the model’s parameters. Google says the model has been part of Chrome since 2024, uses local storage, and automatically uninstalls when system resources run low.

Key Facts Chrome stores approximately 4 GB of Gemini Nano AI model files on users’ devices without their explicit consent. Google states that since February users can disable or remove the model via Chrome settings, and the model will auto‑uninstall if the device is low on resources. Security researcher Alexander Hanff showed that deleting the model triggers an automatic redownload upon Chrome restart on both Windows and macOS, with no user notification.

What It Means For most users the model runs transparently, enabling AI‑powered features without sending data to the cloud. Those concerned about storage or privacy can now toggle the feature off in Settings → System, though the option may not yet be available to all Chrome builds. If the model is removed manually, Chrome will restore it silently at the next launch, potentially affecting available disk space.

Watch for broader rollout of the on‑device AI toggle across Chrome versions and any user‑facing explanations Google may provide in future release notes.