How to chat with a PDF online in Whizi

When to use which model for a PDF

• Gemini 3 Pro has the largest context window and handles very long PDFs (contracts, research papers, 100+ page reports) without chunking.

• Claude Sonnet is best when you need nuance: legal documents, policy briefs, long narrative text.

• GPT is fast for short PDFs, invoices, and structured data extraction.

Whizi lets you switch between all three inside the same upload, so you do not have to guess.

Prompt ideas that actually work

• "Summarize the attached document in 10 bullet points, then list the three claims that need verification."

• "Extract every date, dollar amount, and contract party from this PDF into a clean table."

• "Compare the attached two contracts and flag every clause that differs."

• "Rewrite the findings section for an executive audience in 150 words."

Troubleshooting

If a PDF is scanned (image-based), ask the model to "OCR and then answer"; Whizi handles OCR automatically for most plans, and you can explicitly request it.

If the file is too large for one model, Whizi will suggest Gemini 3 Pro automatically.

Workflow checklist

• Upload the PDF
• Pick Gemini or Claude for long files, GPT for short
• Ask one question at a time
• Re-run across a second model to verify

Common questions