Chrome Secretly Downloaded a 4 GB AI File to Millions of PCs — Without Asking

Chrome Secretly Downloaded a 4 GB AI File to Millions of PCs — Without Asking

Google’s browser has been quietly installing Gemini Nano, its on-device AI model, onto users’ computers — consuming up to 4 GB of storage and processing power, with no notification and no consent prompt.

Users who have noticed their free disk space mysteriously shrinking may now have an explanation: Google Chrome has been silently downloading a large AI model called Gemini Nano onto some users’ computers — without permission, and without any notification whatsoever.

The discovery was first reported by the US technology outlet CNET, and has since drawn sharp criticism from privacy advocates who argue the practice is both ethically problematic and potentially illegal under European data protection law.

What is Gemini Nano?

Gemini Nano is an AI model developed by Google designed to run directly on a device — on a laptop or smartphone — rather than in the cloud. By processing everything locally, it can operate even without an internet connection and without sending data to Google’s servers.

Within Chrome, Gemini Nano powers features such as writing assistance (“Help me write”), detection of fraudulent websites and phishing messages, page summarisation, and tab group suggestions. Starting with Chrome 149, the model supports English, Spanish, Japanese, German, and French.

It is important to distinguish Gemini Nano from Chrome’s “AI Mode” button in the address bar: AI Mode connects to Google’s remote cloud servers, whereas Gemini Nano runs entirely on your own machine — potentially in the background, even when you are not actively using any AI feature.

Why did Google install it without warning?

Alexander Hanff — a Swedish computer scientist, lawyer, and privacy campaigner known online as “That Privacy Guy” — offered a pointed explanation to CNET.

“By having users perform inference processing on their own hardware, Google can provide ‘AI functionality’ without incurring computational costs.”

— Alexander Hanff, privacy advocate and computer scientist

“Inference” is the process by which a trained AI model performs a task — answering a question, analysing text, detecting fraud. Normally this computation happens inside Google’s data centres. By shifting that burden to the user’s own CPU or GPU, Google avoids the associated electricity and hardware costs — while the user bears slower performance, higher battery drain, and a file of up to 4 GB consuming their storage.

“Google has repeatedly violated privacy globally for the past 20 years. They likely judged that requesting permission — as required by law — would hinder the widespread adoption of this model.”

— Alexander Hanff

Hanff further argues that installing software on a user’s device without consent may violate the “legality, fairness, and transparency” principles enshrined in the EU’s General Data Protection Regulation (GDPR). Perhaps reflecting these regulatory concerns, Google has paused the rollout to EU users; other regions — including Japan, and users across North America and Asia — remain targeted.

A Google spokesperson told CNET that since February the company has offered a setting to turn off and remove the model from within Chrome’s settings, and that disabling it will prevent future downloads. They also noted the model is automatically removed if the device falls below minimum hardware thresholds.

How to check if it is on your computer

As Hanff points out, Chrome provides no notification, so you will not know Gemini Nano is present unless you look. The quickest method for any platform is to type chrome://on-device-internals into the Chrome address bar and inspect the Model Status tab. You can also look directly for the file:

How to remove Gemini Nano

Hanff’s strongest recommendation: the most reliable way to ensure Gemini Nano does not return is to uninstall Chrome entirely and switch to an alternative browser.

Hardware requirements and automatic removal

Google states that Gemini Nano is only downloaded if a device meets minimum specifications:

According to Google, weights.bin is automatically deleted when free storage drops below 10 GB, and also removed if hardware requirements are not met for 30 consecutive days. Privacy advocates advise against relying on this mechanism and recommend manual removal instead.

To put the file size in context: 4 GB is equivalent to roughly 1,000 to 2,000 smartphone photographs. The silent installation of a file of this magnitude — with no user prompt, no notification, and no opt-in — raises serious questions about the boundaries of what software publishers can do on hardware they do not own. Privacy watchdogs say the situation warrants close and continued scrutiny.