Chrome silently downloads a 4GB AI model. Here’s how to remove it

Google’s Chrome browser is already a notorious storage hog, but now comes word that it’s crowding our PC drives in a new way: with a local AI model. That model, spotted by That Privacy Guy, gets silently downloaded to your PC or Mac upon installing Chrome, and it gobbles up a whopping 4GB of storage space.

Spoiler alert: Yes, you can remove the file, and I’m going to show you how. But first, some details on what’s going on.

The specific file is called weights.bin. On my Mac, I found it in Chrome’s Applications Support folder in Finder:

~/Library/Application Support/Google/Chrome/OptGuideOnDevice Model/

Windows users will find the file in the AppData directory:

C:\Users\\AppData\Local\Google\Chrome\User Data\OptGuideOnDeviceModel\

To get to the AppData directory, press Windows Key + R, type %LOCALAPPDATA%\Google\Chrome\User Data\ directly into the dialog box, then press Enter.

On my Mac, the weights.bin file was taking up 4.27 GB of storage. If you delete the file, Chrome will simply reinstall it the next chance it gets.

So, what exactly is weights.bin and what does it do?

As That Privacy Guy notes, that file includes the “weights” for Gemini Nano, the local AI model that lives in Google’s Chrome browser. Unlike Gemini in the cloud, Nano sits directly on your PC and performs a variety of AI tasks directly on your system.

Among the local AI duties that Gemini Nano may handle include summarizing web pages you visit, organizing your Chrome tabs, warning you about online scams, and offering writing help or rephrasing text as you type, according to a Google support page.

Having a local AI model on your machine offers a number of advantages depending on the task, including lower latency and potentially greater privacy (although Chrome may still be sharing at least some of your browser activity with Google HQ).

But local models also take up a lot of storage space. Gemini Nano’s 4GB footprint actually isn’t bad as far as smaller local models go—the 31 billion-parameter version of Google’s Gemma 4 takes up 20 GB of storage, for example, while the 128 billion-parameter Mistral Medium hogs a massive 80 GB of space.

Again, simply deleting the weights.bin file won’t work, as Chrome will automatically reinstall the missing file. But you can remove the 4GB download another way: by changing a single Chrome setting. Just go to Settings > System, then toggle the “On-device AI” setting to Off. When I did that on my Mac, the weights.bin file disappeared immediately. 

Of course, turning Chrome’s local AI setting off nixed Chrome’s local AI functionality, including text suggestions and scam warnings. 

As far as Chrome quietly installing the local AI model on your system in the first place, it’s a matter of hot debate. For his part, The Privacy Guy calls out Google for depositing the file on users’ PCs without a consent dialog—and he has a point. 

Moving ahead, though, we’re going to see more and more desktop apps downloading local AI models onto our systems, for better or worse.