The short answer
To summarise a PDF with AI, upload it to a tool that can read the whole file, say why you are reading it and who the summary is for, ask for cited points or quotes, and check the points you will act on. Google's Gemini Notebook, called NotebookLM until July 2026, is the most faithful choice because it answers only from your sources with citations, and its free plan allows 50 sources per notebook. ChatGPT's free plan reads only about 12 pages at a time.
What you need before you summarise a PDF with AI
- The PDF itself, with selectable text if possible. Scanned pages can work, but a text PDF gives cleaner results.
- The reason you are reading it. "Summarise this" gets a generic abstract. "What does this tender require from us, and by when?" gets the summary you need.
- The reader of the summary. Yourself, your manager or a client.
- A quick privacy check. On personal plans, ChatGPT and Claude can use chats for training unless you opt out. For confidential documents, use a work plan or switch the setting off first.
How to summarise a PDF with AI in 7 steps
- Pick a tool that can read the whole file. This matters more than people think. ChatGPT's free plan has a context window of about 27,000 tokens, roughly 12 pages of input, so a long report may only be partly read. Gemini Notebook, Claude and paid plans handle far more. If in doubt, ask the tool to list the last section heading it can see.
- Attach the file, do not paste it. In ChatGPT and Claude, attach it from the message box. In the Gemini app, click Add Files, then Files. In Gemini Notebook, open a notebook and select Add sources on the left.
- Put your question after the document. Anthropic's prompting guide recommends long documents first and the question at the end, and says putting the question at the end improved response quality by up to 30 percent in its tests, especially with complex, multi-document inputs.
- Ask for the summary in the shape you need. "Five bullet points for a busy director, then the three numbers that matter most, then open questions." Specify the length.
- Ask for quotes or page references. "After each point, quote the sentence it is based on." Anthropic recommends grounding long-document answers in quotes to keep them faithful to the text.
- Check the points you will act on. Click the citation or search the PDF for the quote. A summary that skips the one clause that matters is the classic failure.
- Ask follow-up questions. The real value is in the second and third questions: "What does it say about termination?", "Which assumptions are weakest?", "What is missing that I would expect in a document like this?"
A worked example: a 60-page annual report in ten minutes
A finance analyst needs to brief her manager on a supplier's annual report before a contract renewal.
- She creates a notebook in Gemini Notebook and adds the PDF as a source, along with last year's report.
- Her prompt: "Using only these two reports, summarise for a procurement manager: revenue and profit trend, debt, any risks the company flags about its own business, and anything that changed between the two years. Five bullets, then a table of the key numbers for both years with page references."
- The answer arrives with citations. She clicks the two that matter most, the debt figure and a new risk about a lost customer, and confirms them in the PDF.
- Follow-up: "What would a sceptical buyer ask about in this report?" She gets four questions for the renewal call.
- She asks for an Audio Overview in The Brief format to listen to on her commute, then pastes the bullets into her email.
Common mistakes when summarising PDFs with AI and how to fix them
- The tool only read part of the file. Fix: use a tool with a large enough context window, split the PDF, or ask which sections it saw.
- A generic summary. Fix: say why you are reading and who the summary is for.
- Invented details. Fix: tell the AI to answer only from the document and to say "not in the document" when something is missing. See how to reduce AI hallucinations.
- Tables and charts misread. Fix: ask it to reproduce the table first, check it, then analyse.
- Trusting a summary of a weak source. Gemini Notebook's honest catch is that it only knows what you give it, so a one-sided document gives well-cited but one-sided answers. Fix: add a second source.
Which AI tool to use to summarise a PDF
| Tool | Best for | Free plan | The catch |
|---|---|---|---|
| Gemini Notebook (Google) | Faithful, cited summaries of one or many documents | Standard: 100 notebooks, 50 sources each | Knows nothing beyond your sources |
| Claude (Anthropic) | Judgement on what a document means; turning it into a finished brief | Claude Sonnet and Haiku, with limits every 5 hours | Opus 5.5 and Research need a paid plan |
| ChatGPT (OpenAI) | Quick summaries and follow-up analysis | GPT-6 Luna, limited uploads, about 12 pages of input | Free context is small for long PDFs |
| Gemini app (Google) | PDFs alongside Gmail and Drive | Mostly Flash-Lite since 9 October 2026 | 1 million token context needs Google AI Pro |
Our pick is Gemini Notebook for accuracy, because answers are grounded only in your sources, with citations, and it accepts PDF, Word, PowerPoint, Google Docs and more. Pick Claude when you need an opinion on the document, not just a summary. Full detail is on best AI for summarising PDFs, plus the tool guides for Gemini Notebook, Claude and ChatGPT. If the PDF is a research paper, see best AI for research; if it is a contract, see best AI for legal documents.
Privacy when you upload a PDF
On personal ChatGPT accounts, switch off Improve the model for everyone under Settings, then Data controls. On personal Claude plans, switch off Help Improve our AI models under Settings, then Privacy. Gemini Notebook has no training toggle, but Google says personal-account content is not used to directly train its foundational models unless you give feedback, so avoid the thumbs buttons on sensitive notebooks. Work and school accounts get no human review and no training. Read more in our private AI for sensitive data guide.
5 prompts for summarising PDFs
Prompts to copy
Summary for a busy reader
Using only the attached PDF, write a summary for [reader] who needs to [decision]. Give five bullet points, then the three numbers that matter most with page references, then up to three open questions. If something is not in the document, say so.
You get: A decision-ready summary with page references
Quote-backed key points
From the attached document, extract the exact quotes most relevant to [topic], numbered. Then summarise what the document says about [topic] in under 200 words, citing the quotes by number.
You get: A summary you can verify line by line
What it means for us
We are [who you are]. Read the attached [tender, contract, policy] and list what it requires from us, by when and what happens if we do not comply. Rank items by risk to us. Quote the clause behind each item.
You get: Obligations and deadlines ranked by risk
Compare two versions
Attached are [version 1] and [version 2] of [document]. Make a table of every meaningful change: section, old text, new text and what it means in practice. Ignore formatting changes. End with the three changes that matter most.
You get: A change log between two PDFs
The sceptic's read
Read the attached [report] as a sceptical [CFO, buyer, reviewer]. List the five weakest claims or assumptions, quote each one, and say what evidence would be needed to support it. Then list anything important you would expect in a document like this that is missing.
You get: The weak spots before someone else finds them