You open an article to answer one question. Twenty minutes later, you have a report, two product pages, a half-written email, and a chatbot tab that has lost the context. The best AI Chrome extension for that kind of day should help you finish the work already in your browser. Lensia puts a conversation beside the page in a Chrome sidebar, with document attachments and a model picker. Start with the tasks you need that sidebar to handle. Install Lensia free if you want to try the examples as you read.
Start with the task you repeat every day
An extension that excels at correcting grammar may do little for comparing two PDFs. A research assistant might find sources but still need your draft before it can help with an email. Choose a task you repeat often enough to judge the difference.
For a project manager, that might mean finding the decision buried in a long update. For a freelancer, it could be turning rough notes into a clear client reply. Someone learning a new skill may need explanations beside the documentation. Give the assistant one real task, with the material you would normally use, and see whether the result is worth keeping.
Write down what a good result looks like before you install anything. "A summary that preserves the deadline and the exception" is a better test than "something impressive." That small constraint makes it easier to compare tools fairly.
Look for a sidebar you can keep working in
A persistent conversation lets you ask a follow-up without rebuilding the whole prompt. Suppose you are reading a supplier proposal. Your first question identifies the main offer. The next asks which requirements remain unanswered. A third turns those gaps into questions for the supplier. Those are parts of the same task, so keeping them together matters.
In Lensia, click the extension's toolbar icon to open sidebar chat. Sign in with Google, then supply the relevant material or ask about the current page. If the assistant cannot read what you need, paste the passage or attach the document. Check which material the answer actually used before continuing.
Conversation history helps you return to earlier work, and bookmarks give you a place to keep answers you will need again. Keep unrelated projects in separate conversations so a detail from one client does not creep into another client's reply.
Compare tools by the features you will use
There are several established approaches to browser AI. Sider presents a sidebar with multiple models and reading tools. Merlin's Chrome listing emphasizes research, rewriting, and summaries. Lensia combines sidebar chat, attachments, and model selection, with web search on paid plans.
These descriptions help narrow the shortlist; they are not a hands-on ranking. Features and allowances can change, so check each product's current details before paying.
- Can you ask another question about the same material?
- Does it accept the documents you actually work with?
- Can you identify the source behind an answer?
- Are useful features included in the plan you would choose?
- Is the result easy to move into your own notes or draft?
The model picker is useful when different tasks need different kinds of help. A short rewrite and a careful document comparison do not have to use the same model. Our multi-model sidebar guide explains how to make that choice without turning every prompt into an experiment.
Give your shortlist the same small test
Use material you can comfortably share. A public article, a sample report, and a draft with personal details removed are enough for an initial comparison.
- Open the same article in Chrome for each assistant.
- Ask for a brief summary with the main claim and its supporting evidence.
- Ask a follow-up about an exception mentioned in the article.
- Supply a short email draft and ask for a clearer version with the facts unchanged.
- Compare the results with the originals and note what you had to correct.
Pay attention to follow-up quality. An assistant that gives an attractive first answer but forgets the constraint on the next turn may leave you doing more work. Also notice whether it invents details to fill gaps. A useful answer can say the material does not contain what you asked for.
For a more focused reading test, use the prompts in our article summarizer guide. If documents are your main workload, start with the PDF summarizer walkthrough instead.
Check the limits before choosing a plan
Lensia's Free plan includes sidebar chat, conversation history, bookmarks, Essential models, and PDF attachments within its allowance. PDFs attached to one message can total up to 2 MB on Free, 10 MB on Basic, or 20 MB on Pro, with up to five PDFs per message. A large report can therefore require a different plan or a smaller excerpt.
Basic adds web search and URL fetching, Advanced models, and Custom Instructions. Pro adds Frontier models and opt-in Agentic Mode for browser tasks involving multiple steps. Ordinary sidebar chat does not require Agentic Mode.
Free has a starter usage allowance, Basic offers about ten times that allowance, and Pro has the highest allowance. Longer inputs or different models can consume different amounts. Start with the smallest plan that fits the task you tested. You can compare plans after you know which features you need.
Keep privacy part of your everyday routine
Browser AI uses the content supplied to answer your request. An uploaded PDF or pasted email may contain more than the paragraph you care about. Remove irrelevant account details and use a public example when you are evaluating a tool.
Read the privacy policy for how Lensia handles submitted content and service data. Do not assume a browser sidebar means all processing happens on your computer. If your workplace has rules for sharing documents with AI services, use those rules to choose what to submit.
Pick one workflow and finish it
Your first successful task can be small: understand an article, shorten an email, or find the difference between two document sections. Keep the source beside the sidebar and judge the result against what you needed to accomplish. If that works, try the same approach on tomorrow's task.
Try Lensia in Chrome with one piece of work you already wanted to finish.