Brain in Vat Chrome Extension
Answers questions about any webpage using OpenAI, keeping everything stored locally for privacy.
At a glance
Starts at
Free
No paid plan found on the Chrome Web Store, September 2026.
Free tier
Yes
Platforms
Chrome
Best for
Developers wanting an open-source, privacy-first web reading aid
Not for
Anyone wanting a polished tool with an established user base
3.9 out of 5
Scored by a Toolio reviewer after real useOur verdict
Brain in Vat reads a webpage and answers questions about it on demand, routing the AI work through OpenAI while keeping your data stored locally rather than on a server. Being open source, anyone can inspect exactly how it handles that data. It has no ratings yet, so it's essentially untested outside its own codebase.
βWhat it does well
Local data storageStores your data locally instead of on a remote server.
On-demand answersAnswers questions about webpage content on demand.
Open-source codePublishes its code openly for anyone to inspect.
βWhere it falls short
Unproven track recordHas no ratings yet to gauge real-world reliability.
Requires OpenAI accessDepends on OpenAI's API to generate any answers.
Chrome onlyWorks only as a Chrome extension, without other browser support.
Key features
Webpage Q&AAnswers questions about the content of any open webpage.
OpenAI integrationRoutes questions through OpenAI to generate answers.
Local storageKeeps collected data stored locally on your device.
Open-source codebaseMakes its full source code available to inspect.