You download a report because it looks relevant, then stop at the contents page. An AI PDF summarizer gives you a way into the document: ask what it covers, find the sections relevant to your question, and work through them in a conversation. Lensia accepts PDF attachments in its Chrome sidebar, so the file and your follow-up questions can stay in one thread. Install Lensia free to try the workflow with a document you can comfortably share.
Start with a question the document can answer
A whole-document summary is useful for orientation. It is less useful when you already know what you need: the launch requirements in a manual, the changes between two proposals, or the method used in a research paper.
Write that question before attaching the file. For a project report, you might ask: "What does this report say about the delayed milestones? Summarize the reasons given and identify any next steps. Use only the attached document."
That prompt gives the assistant a clear boundary. If the file does not explain a delay, the answer should say so. Ask it to flag missing information rather than fill the gap with an explanation that merely sounds plausible.
For an unfamiliar PDF, start with its structure instead: "Give me an outline of the main sections and tell me which ones discuss implementation costs." You can then ask a narrower question about the relevant section without rereading the overview.
Attach the PDF to sidebar chat
Click Lensia's toolbar icon in desktop Chrome, sign in with Google, and open a conversation. Use the sidebar's attachment control to choose the PDF, wait for the attachment to finish, then send your question with it.
- Select the document you want to discuss.
- Check the filename shown in the attachment preview.
- Write a question with a clear topic and preferred answer length.
- Send it after the attachment is ready.
- Ask for the relevant passage or section when you need to verify a detail.
PDF attachments are available on every tier, with different limits. Up to five PDFs can accompany one message. Their combined size must fit within 2 MB on Free, 10 MB on Basic, or 20 MB on Pro. These limits apply to the total, so two 1.5 MB PDFs exceed the Free limit even though each file is small by itself.
If your file is too large, use a smaller document or provide the section needed for your task. You can compare plans if larger attachments are a regular part of your work. Attaching a short relevant excerpt can also make the conversation easier to manage.
Get an overview that preserves useful details
Choose the overview to fit the document. A meeting report needs decisions and open actions. A product manual needs prerequisites and the sequence of steps. A paper needs the research question and how the authors investigated it.
Try a prompt with a format: "Summarize this report in four short sections: purpose, main findings, limitations, and open questions. Preserve dates and quantities when they affect the conclusions."
Ask for section references so you know where to look next. Treat those references as pointers to check, rather than guaranteed citations. The assistant may confuse a PDF viewer's page number with the number printed on the document, or misread a heading.
If you want to read online articles with the same approach, our article summary guide shows how to keep an argument and its evidence distinct.
Compare documents using a shared question
Two PDFs are easier to compare when you tell the assistant what counts as a difference. "Compare these" can produce a general overview that misses the deadline or excluded service you actually care about.
For two proposals, label them by filename and ask: "Compare Proposal A and Proposal B on scope, delivery dates, ongoing support, and exclusions. Keep each document's claims separate. Mark anything not stated."
Follow up on one row at a time. If a proposal mentions support but does not specify response times, that is an unanswered question. A table that says "not stated" is more useful than one that invents a reasonable-sounding service level.
Keep document names visible in your prompt and in the answer you save. That helps prevent a number from one proposal being attributed to the other. For a wider search across public sources, see our research workflow.
Work carefully with tables and scanned pages
Tables need their labels
A table may include a unit in the heading and an exception in a footnote. Ask the assistant to explain those before interpreting the values. For example: "Read the table's column headings and footnotes first. What period and units do the values represent?"
If a number matters to your next step, compare it directly with the PDF. Columns can shift during reading, and a subtotal can look like a final total when the surrounding context is missing.
Scans can be difficult to read
A scan of a printed page may be blurry or contain handwriting. Ask whether the text is readable before requesting a detailed answer. If a line is unclear, supply a cleaner copy or type the short passage yourself.
An unclear source needs a better input. Switching models may help with some documents, but it cannot reliably recover text that is absent or illegible. Our model selection guide explains when a different model is worth trying.
Turn an answer into something you can use
After you understand the document, ask for an output suited to your next task. A list of questions for the author, a reading checklist, or a short explanation for your team can be more useful than another summary.
- Ask which requirements still need clarification.
- Request a glossary of unfamiliar terms from the document.
- Turn the stated steps into a checklist, retaining prerequisites.
- Ask for the assumptions behind one recommendation.
Keep the original file available when you save the result. Conversation history can help you return to the discussion, but your own notes should identify the filename and version. If an updated PDF arrives later, start by making that change explicit rather than letting the thread mix versions.
Try one document before building a bigger routine
Use a public report or a personal document with private details removed. Ask one focused question, check its answer, then ask one follow-up. Uploaded content is processed to generate replies; read the privacy policy before sharing sensitive material.
You do not need an elaborate prompt to start. "Explain the installation requirements in this manual and point me to the relevant section" is enough to judge whether the sidebar helps with your reading.
Install Lensia and ask your PDF the question that made you download it.