How to redact a PDF properly (and why black boxes fail)
Updated 2026-10-25
A black shape drawn over a name or account number in most editors only hides it. The original text is still in the file, and anyone can select it, copy it, or remove the shape. Court filings and government reports have leaked this way repeatedly.
Proper redaction removes the underlying content, so there is nothing left to uncover.
Step by step
- 1Open Redact PDFSelect the document. It is processed in your browser, so the sensitive version never leaves your device.
- 2Mark what must goDraw over the text and images that must be removed — names, account numbers, addresses, signatures.
- 3Apply and verifyDownload the redacted copy, then try to select or search for a redacted word. It should not be found.
Things people forget to redact
Headers and footers repeated on every page; the same number written again in a table later in the document; signatures and handwritten notes; and the file name itself, which often contains a person's name.
Questions
- Can redaction be undone?
- Not from the redacted copy — that is the point. Keep the original somewhere safe in case you redacted too much.
Your file stays on your device the whole time.
Also useful: Edit PDF · Protect PDF