Whiteout and redaction: what actually disappears?

A page has more than its appearance

A PDF can contain text, images, metadata, links, form fields and attachments. What you see on screen is only part of the file. Drawing a coloured rectangle over a passage changes its appearance but does not necessarily remove the original content. This matters when the document contains addresses, identifiers or information that should not be disclosed.

What whiteout does

FOLD’s Erase tool is a visual cover. It can be useful for tidying a layout or preparing a cosmetic correction, but the source text stays in the exported file. Someone may still select it, copy it or recover it with another tool. A cover should never be mistaken for a confidentiality measure.

What page redaction does

In the documented FOLD implementation, pages carrying redactions are rebuilt as images. The marked regions are painted into those images and the original page text layer is discarded. Pages without redactions are passed through. This approach changes the redacted page’s searchability and can increase its size. It is also why the exported result should be treated as a new document.

What to check after export

Open the downloaded PDF, inspect every redacted region and test whether the removed words can still be selected or found. Review metadata, attachments, bookmarks and other pages separately: page redaction does not remove those. Keep the original in an appropriate location and share only the reviewed output. The tool makes no claim to satisfy a specific legal redaction standard.

A worked example: sharing a payment receipt

Imagine a receipt containing an account number, a transaction reference and a delivery address. First decide which details the recipient actually needs. Keep the source receipt and mark the unnecessary information for redaction. Check for repeats: the same account number may appear in a header, a note or another page. Export the redacted copy and verify every occurrence. A neat black bar on the preview is not the verification step; the downloaded file is. If the receipt has an attachment or embedded metadata, review that separately. FOLD’s page redaction does not sanitise the entire document container.

Choose the right operation

Your goal	Suitable approach	What to verify
Tidy a non-sensitive layout	Whiteout or an annotation	The cover looks correct
Remove private content from a page	Redact, then inspect the export	The original page text is gone
Remove an entire unnecessary section	Split or organise pages	The section is absent
Sanitise document metadata or attachments	A separate inspection and removal process	Non-page data is reviewed

Troubleshooting the output

If search still finds the sensitive words, confirm you opened the exported copy rather than the original. Check whether an occurrence was missed on another page. If a redacted page looks soft, compare the export resolution options and the source scan quality. Raising resolution can improve the rendered page but cannot restore detail missing from the original. If the output becomes larger, that can be a consequence of rebuilding a previously compact text page as an image. Keep this trade-off separate from whether the marked content was actually removed.