Disable Download Local AI Modal in Google Chrome

As of May 2026, Google Chrome has been observed automatically downloading a local AI model (Gemini Nano) of approximately 4GB, named weights.bin, into a folder called OptGuideOnDeviceModel without explicit user consent.

Here are the most effective ways to disable this and remove the files:

Method 1: Disable AI Features in Chrome Settings (Recommended)

This is the official way to stop the download and remove existing models.

1. Open Chrome and go to Settings (three-dot menu, top right).
2. Navigate to System on the left menu.Toggle "On-device AI" to Off.
3. Relaunch Chrome.

Method 2: Use Chrome Flags (Forced Method)

If the setting above does not stop the re-downloading, you can disable the underlying experimental flags.

1. Type chrome://flags into the address bar.
2. Search for: "Optimization Guide On Device" and set it to Disabled.
3. Search for: "Prompt API for Gemini Nano" and set it to Disabled.
4. Relaunch Chrome.

Method 3: Delete Existing Files (Windows & Mac)

After using Method 1 or 2, you can delete the existing 4GB model to free up space.

• Windows: Navigate to %LOCALAPPDATA%\Google\Chrome\User Data\Default\OptGuideOnDeviceModel and delete the contents.
• macOS: Locate ~/Library/Application Support/Google/Chrome/Default/OptGuideOnDeviceModel.

Important Note

If the file is deleted without disabling the settings, Chrome may automatically re-download it. The methods above are designed to make the removal persistent.