Google Chrome’s new on‑device AI model, Gemini Nano, quietly swallows about 4 GB of hard‑drive space when enabled. The model lives in a weights.bin file inside Chrome’s OptGuideOnDeviceModel folder, and users report unexplained storage drops after turning on features like scam detection or autofill. Chrome installs the file automatically, without a clear warning about its size.

Because Gemini Nano runs locally, it stores training parameters on the device instead of querying the cloud, giving privacy benefits but forcing the 4 GB requirement. Google says the exact size may shift with updates, yet the information appears only in a lengthy help guide, not at the toggle. The model will uninstall automatically if storage is tight, but only after a toggle is disabled.

Users wishing to reclaim space can disable the on‑device AI option in Settings > System, which stops future downloads. Chrome will delete the weights.bin file once the feature is off, but it cannot be removed manually while the feature remains active. Google’s spokesperson Scott Westover noted the model will auto‑uninstall on low‑resource devices, ensuring users aren’t stranded with unwanted data. This behavior highlights the trade‑off between local AI convenience and disk usage.