How-to
How to use AI on a scanned PDF without exposing personal information
A scanned PDF is a picture of text, so search and find-and-replace cannot see the names in it. Run OCR first to turn the scan into text, find and replace personal details in that text, then review it against the scan, because OCR misreads names and numbers. Share only the reviewed text with the AI, never the original scan.
Last reviewed · 2 sources
Why scans are harder
When you upload a scan to an AI assistant, the assistant can read the image, including every name, signature and handwritten note. Your own tools often cannot: Command-F finds nothing in an image-only PDF, so a quick visual check is all that stands between the details and the AI.
OCR, optical character recognition, converts the image into text. It makes mistakes, especially with faint copies, stamps, handwriting, tables and unusual names, and a misread name will not match a search for the real one.
A safer workflow for scans
- Run OCR on your own computer rather than in an online converter.
- Detect and replace names, addresses, dates and ID numbers in the recognized text.
- Compare the text with the scan page by page, looking for misread names and numbers.
- Check the places OCR skips: stamps, handwriting, signatures, photos and margins.
- Share the reviewed text, not the image, with the AI.
Budget more review time
Expect to spend longer reviewing a scan than a born-digital PDF. Misses concentrate where recognition is weakest. If a page is barely legible to you, assume the OCR missed something on it.
Where PiBye fits
How PiBye handles this
PiBye runs OCR on scanned PDFs on your Mac, in English and French, then detects personal details in the recognized text so you can approve each replacement. Nothing is uploaded for recognition.
Scanned pages are where detection is least reliable, so PiBye asks you to read the complete copy before approving it for AI use.
1.0.1 · macOS 14.8.5 or later · Apple Silicon · 1.1 GB
Frequently asked questions
Can the AI read a scanned document I upload?
Yes, modern assistants read images, so everything visible in the scan, including names and signatures, is shared.
Is online OCR safe for client documents?
Online OCR uploads the scan to another service. For client documents, run OCR on your own computer.
Does OCR read handwriting?
Much less reliably than printed text. Review handwritten notes, signatures and stamps by eye and remove anything identifying.
Sources
- Licensee use of generative artificial intelligence (white paper), Law Society of Ontario, April 2024. Checked 17 September 2026.
- Principles for responsible, trustworthy and privacy-protective generative AI technologies, Office of the Privacy Commissioner of Canada, December 7, 2023. Checked 17 September 2026.