The best AI Chrome extension is the one that is already there when you need it, sitting next to your work instead of in another tab you have to go find. That is the whole idea behind Lensia. It puts an AI assistant inside Chrome with two ways to use it: a sidebar chat that stays open beside any page, and a floating panel you pull up to get a fast answer about anything on your screen. No copying links into a separate chatbot, no losing your place. Research, a dense report, an email you need to rewrite: the help is right where you are looking. Install Lensia free.
The sidebar chat is where the work happens
The sidebar chat opens next to whatever page you are on and stays there while you work. It holds a real conversation instead of a single reply, so you can ask something, read the answer, push back, and keep going until you actually have what you needed.
A few things make it the surface you will live in:
- Conversation history sticks around between sessions, so a thread you started this morning is still there this afternoon.
- Bookmarks save the answers worth keeping so they are not buried three topics back.
- A model picker lets you start on a fast model and switch to a stronger one mid-conversation when a problem gets harder.
Because it keeps the whole thread, the sidebar is the right tool for anything that takes more than one question: talking through a decision, breaking down a long document section by section, or working out why a chunk of code is failing. For a full look at how it fits together, read how Lensia works.
The floating panel for a fast answer
Sometimes you do not want a conversation, just a quick answer about the thing in front of you. Press Ctrl+Shift+X, drag a box around it, and an answer appears on top of the page in a couple of seconds. It is the fastest way to explain a confusing paragraph, a chart, or an error message without leaving what you are reading.
The panel does a bit more than one-shot answers. Ask Mode turns it into a box where you type your own question and attach up to three images, which is handy when one screenshot will not carry the whole thing. Ctrl+Shift+F repeats your last capture for a page of similar items, and Ctrl+Shift+E hides the panel when you want a clean screen.
What you can actually do with it
The point of a good AI extension is not the tech, it is what it saves you. A few things people reach for Lensia to do:
- Read faster. Drop a long article or report into the sidebar and ask for the gist, then dig into the parts that matter. More on that in summarizing articles and web pages with AI.
- Research without the tab sprawl. Ask questions as you browse and keep the thread in one place. See using AI for research.
- Write and rewrite. Draft a reply, tighten a paragraph, or change the tone of something without switching apps. See an AI writing assistant in your browser.
- Make sense of code and errors. Capture a stack trace or a function and ask what it means and how to fix it.
Light, private, and out of the way
A browser extension should not slow Chrome down. Lensia installs at around 12 MB, where a lot of AI extensions run 50 to 90 MB. It also only does something when you ask it to, so it is not watching your browsing in the background. If privacy is what you care about most, here is a closer look at how it handles your data.
Free to start, more when you need it
You sign in with Google and you are in. Free covers the sidebar chat with history and bookmarks, the floating panel with Ask Mode, the Quick and Standard models, and the Lensia Max router, which picks a good model for each question on its own.
| Plan | Usage | What it adds |
|---|---|---|
| Free | Starter | Sidebar chat, floating panel, Ask Mode, Quick and Standard models, Lensia Max |
| Basic | About 10x Free | Web search, fetch URL, custom instructions, a reasoning toggle, and Advanced models |
| Pro | Highest | Agent mode, which lets the AI read your open tabs and chain a few steps before it answers |
Most people are fine on Free or Basic. Pro is for heavier use and the times you want the AI to do more of the legwork itself. For a side-by-side of the plans and models, read the full plan comparison.
Getting started
Setup takes under two minutes. Install Lensia from the Chrome Web Store, sign in with Google to activate, and open the sidebar on whatever you are working on right now. Then try the floating panel the next time something on a page stops you.
The best AI Chrome extension is the one you actually use, and you use the one that is already next to your work. Install Lensia today and put it next to yours.