This is not a theoretical risk
There is a well-known series of cases in which published court and government documents were read exactly this way — names, addresses and amounts could be recovered with a few clicks, although the page looked redacted.
Check your own document
It takes twenty seconds:
- Open the supposedly redacted PDF in any viewer.
- Drag the mouse across the black rectangle as if you wanted to select text.
- Copy the selection with Ctrl+C (Mac: Cmd+C).
- Paste it into a text editor.
If the text you wanted to redact appears there, the document is not redacted. It only looks that way.
A second route is the text search: search the document for a word you know sits under the rectangle. If it is found, it is still there.
Why this happens
A PDF file stores text and graphics separately. A rectangle is a graphic object lying on top of the text — much like a sheet of paper lying on a letter. Lift the sheet, and the writing is still there.
The same goes for other obvious approaches. A black highlighter in a PDF program is an annotation that can be removed. White text on a white background is still copyable text. Exporting or printing the file does not reliably remove the text either, as long as the text layer survives.
What real redaction means
For a passage to be truly unreadable, two things have to happen:
The text must be removed from the file, not covered. The characters in question are deleted from the page content, so that no search and no copy can find them any more.
The area must be replaced, so that no remnants of the original rendering survive. WipePDF rebuilds the page with the redacted area and embeds it as an image. After that, no text information exists at that spot — only black surface. WipePDF then re-recognises the remaining text on the page and lays it invisibly on top, so the document stays searchable.
You can verify it with the same test as above: select, copy, paste. After real redaction, nothing comes out.
Where this matters most
Wherever redacted documents leave the building: access to files, subject access requests under the GDPR, receipts for authorities, documents for landlords, publications. In all these cases someone hands over a document assuming certain information has been withheld.
For professions bound by confidentiality the difference is not cosmetic. A document that looks redacted but is not is a document handed over without redaction.
And your file stays with you
Documents that need redacting contain, almost by definition, something worth protecting. It would be absurd to upload them to someone else's server for that purpose.
WipePDF works entirely in your browser. The file is opened, edited and saved without leaving your computer. You can verify that: load the page, switch on flight mode, and redact. It keeps working.
Select PDF
Frequently asked questions
Isn't it enough to print the PDF and scan it again?
That does work, but it is cumbersome, costs quality and makes the document unsearchable. A stopgap for single pages, no solution for regular work.
Can redacted areas be recovered from the image?
Not with real redaction. The information is removed, not covered. It is different with pixelation or blurring — a remnant of the original structure survives there, from which something can sometimes be reconstructed. That is why WipePDF redacts with a solid surface instead of pixelating.
Is the metadata kept?
Check that separately. Author name, title and editing traces sit outside the visible page content and are a topic of their own.
How do I know it worked this time?
Select, copy, paste into a text editor. If nothing comes out, nothing is left.