How to redact a PDF so the text is really gone
Remove sensitive information from a PDF permanently, instead of covering it with a black box that can be undone.
Drawing a black rectangle over text does not remove it. In most editors the words are still in the file underneath and can be copied straight back out. This is the single most common way documents leak.
Steps
- Open the PDF in the editor.
- Choose the Redact tool.
- Drag a box over everything that must go. Repeat for each area.
- Choose Export → PDF.
What actually happens on export
Any page carrying a redaction is converted to an image with the boxes burned into it, and the original page — text, fonts and all — is left out of the exported file entirely. There is nothing underneath the black box to recover, because the page it came from is not in the file.
If that conversion cannot be completed for any reason, the export stops with an error rather than falling back to drawing a box over live text.
Good to know
- A redacted page becomes an image, so its text is no longer selectable or searchable. That is the point, but check it is acceptable for your use.
- Redact before you share. Always reopen the exported file and try to select the text where the black boxes are — it should select nothing.
- Remember that a file name, or the surrounding sentence, can give away what you redacted.