How to check whether a PDF is actually redacted
If the downloaded output still exposes text that should have been removed, it needs further work. The reverse is not proof of complete redaction: no text match cannot establish that the file is safe. Combine these methods with visual review, metadata inspection and explicit check coverage.
Method 1: Select-all and copy (fastest)
Open the output in any PDF reader, press Ctrl/⌘+A to select all, Ctrl/⌘+C to copy, and paste into a plain-text editor.
If the names, numbers, or addresses you thought were hidden show up in the paste, the box is merely sitting on top and the text objects remain — that's fake redaction.
Method 2: Keyword search
Use Ctrl/⌘+F in the reader to search for a specific term you redacted (a name, the last digits of a card).
A match for content intended for removal means that text remains extractable. OCR is a different check for visible image text; this site's output workflow does not run OCR.
Method 3: Open it in a different reader
Some viewers render the black box faithfully; others reveal the layer beneath. Open it once in your browser's built-in PDF viewer and once in a separate reader.
If the box turns translucent or the text surfaces in either, the leak is confirmed.
Also review the output checks
PrivScrub rereads the actual generated file to check extractable text, supported document Info values, XMP presence and PDF structures, reporting the actual hash and page scope. Its separate inspector searches supplied exact target strings only in extractable text and supported Info values. It does not run OCR, search XMP contents or detect dark boxes.
Passing applies only to the listed checks. Missing targets, incomplete checks and image content must not be counted as passing. A file hash identifies the output; it is not a safety certificate.
Current PrivScrub PDF scope
PDF editing supports basic, unencrypted files up to 50 pages and 25 MiB. Nonempty annotations, internal or external links, forms, attachments, actions and layers are unsupported and stop processing before export. Redaction rebuilds every page as an image, removing searchable and accessible text from all pages. Metadata removal retains supported page content. Output checks reread the actual file, cover only listed items, and do not run OCR. Visually review every output page.
Questions
The box looks fully opaque — do I still need to check?
Yes. Appearance does not establish that underlying content was removed. Combine text checks with visual review of every page; no text findings do not rule out missed information in images.
Does printing and re-scanning count as redaction?
Printing and rescanning changes the text layer and image quality, but does not automatically cover visible sensitive information. A scan may also acquire a new OCR text layer. Check the final file rather than relying on the production method.