If your Mac’s storage has been mysteriously decreasing recently and you’re using Google Chrome, you may have already identified the culprit. The browser downloaded a 4 GB AI model file to computers without the user’s explicit consent. Here’s how to reclaim the space.
The file in question is called “weights.bin”, which powers Google’s Gemini Nano AI model on the device – the engine behind Chrome features like scam detection, autofill suggestions and the “Help Me Write” tool. Local models tend to be quite large in terms of storage, and this one is no different. The problem is that Google hasn’t clearly reported that it’s consuming 4GB of your hard drive with training data.
The problem only recently came to light thanks to security researcher Alexander Hanff, who noticed that Chrome installs the pattern on any device that meets the minimum hardware requirements, without asking you if you want it in the first place.
How to check if the file is on your Mac
The first thing to do is confirm that the model actually takes up space on your machine. While there is no clear answer in Google’s release notes, recent reports suggest that the file started appearing after updating to Chrome version 148.0.7778.97. Here’s how to tell if your computer has been affected:
- Open Finder, then click Go in the menu bar.
- Hold it Option key and click Library in the drop-down menu.
- Open App support ➝ Google ➝ Chrome ➝ Default.
- Find a folder named “OptGuideOnDeviceModel”.
If the folder exists and contains a file called weight.bin, the template is installed. You can right-click on the file and choose Get information to confirm its size. If the folder isn’t there, you can relax: Chrome hasn’t downloaded the template to your Mac.
How to permanently delete 4 GB file
Simply deleting weights.bin from Chrome’s library folder is not a long-term solution, as Chrome will likely silently redownload it the next time you launch the browser. To make the removal permanent, you need to disable the AI features on Chrome’s device.
- Open Chromium.
- Click the three-dot menu in the upper right corner, then choose Settings.
- In the left sidebar, click System.
- Disable On-device AI.
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Once this setting is disabled, Chrome will remove the template and should stop downloading it in future updates. Remember that removing the template will also disable any Chrome features that depend on it.
If you don’t see the toggle in Chrome’s settings, it probably hasn’t spread to your computer yet. In this case, type chrome://flags in Chrome’s address bar and turn off any AI-related flags you see, then delete the weights.bin file manually in Finder. If after that you’re still concerned about the lack of consent, it might be worth switching to another browser.