AI for Spreadsheets: Formulas, Cleanup and Analysis
How to use AI with Excel and Google Sheets: writing and explaining formulas, cleaning messy data, summarising tables and checking results, with prompts to copy.
How to Summarise PDFs With AI Safely
How to use AI to summarise PDFs, reports and contracts accurately: prompts, checking for missed or invented details, privacy settings and what to never upload.
Key takeaways
- Tell the AI who the summary is for and what you need to decide.
- Ask for page references and direct quotes so you can verify key points.
- Don’t upload confidential or personal documents to tools your organisation hasn’t approved.
On this page
AI can turn a 60-page report into a one-page brief in seconds. Used carelessly, it can also miss the one clause that matters, or invent something that isn’t there; our guide to AI hallucinations explains why. Here’s how to get summaries you can trust.
Step 1: Check the document is safe to upload
Before uploading, ask:
- Does it contain personal data, client information or trade secrets?
- Does my organisation allow this tool for this kind of document?
- Can I remove sensitive parts or use an approved enterprise tool instead?
For highly sensitive material, consider a model that runs on your own device; see how to run AI models locally.
Step 2: Write a purposeful prompt
Generic “summarise this” prompts produce generic summaries. Instead:
“Summarise this report for a finance director who needs to decide whether to renew the contract. Give: a five-bullet summary, the key risks, any deadlines or obligations, and anything unusual. Include page numbers for each point.”
Step 3: Ask for evidence
Request page references and short direct quotes for important claims. It makes checking fast and exposes invented details.
Step 4: Verify the essentials
Open the document and check:
- Numbers, dates and names
- Obligations, penalties and deadlines
- Anything that surprises you
Step 5: Ask follow-up questions
- “What does the document say about termination?”
- “List everything that requires action from us.”
- “What’s missing that I would expect to see in a document like this?”
Common failure modes
| Problem | How to catch it |
|---|---|
| Missing sections in long files | Ask for a section-by-section outline first |
| Invented details | Require quotes and page numbers |
| Tables and charts misread | Check figures against the original |
| Scanned PDFs misread | Make sure the text is selectable, or run OCR first |
Don’t use AI summaries as legal or financial advice
Summaries help you read faster; they don’t replace professional review of contracts, legal documents or financial statements.
For more prompt techniques, see our prompt engineering guide; to understand how assistants answer from your documents, read RAG explained.
Frequently asked questions
Can AI read scanned PDFs?
Many tools can, using text recognition, but accuracy varies. Check tables and numbers carefully.
How long a PDF can AI summarise?
It depends on the tool. Very long documents may be split or partly skipped, so ask for a section-by-section summary.
Is it safe to upload contracts to AI?
Only to tools approved for confidential documents. Otherwise remove sensitive details or use an approved enterprise or local tool.
Sources
Every article is edited by a human and checked against our editorial policy. Spotted a mistake? Tell us.
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