How to Delete or Black Out Text in a PDF (So It's Really Gone)
Need to remove an ID number, a name or an account number from a PDF before you send it? The usual trick, drawing a black box over it, doesn't actually delete anything. Here's why, and how to remove text so it's really gone from the file.
Why a black box isn't enough
When you draw a black rectangle or a black highlight in Word, Mac Preview, a PDF editor or any markup tool, the box sits on top of the text. The text itself is still in the file. Anyone who receives it can:
- select the area and copy it. The "hidden" text pastes in full.
- search the file with Ctrl+F and find it.
- open the file in a PDF editor and move the box aside.
This isn't theoretical. Government and court documents have leaked exactly this way.
How to remove it for real
Proper redaction deletes the text from the file first, then draws a black box where it was. To do it:
- Open Redact PDF and upload the file.
- Type what you want to hide. Separate several items with commas, for example:
123456782, Dana Levi, 12-345-678901. - Download the file. Every occurrence of every item, on every page, is deleted and blacked out.
A thirty-second check
After redacting, open the new file and:
- search with Ctrl+F for what you hid. There should be no results.
- select the black box and copy. There should be no text there.
If something still turns up, it's probably written slightly differently in the file, for example with spaces (123 456 782) or dashes. Add that version too and run it again.
What if the document is scanned?
In a scan, the text is part of the image, so there's nothing to search for. Run the file through OCR first and choose Searchable PDF, then redact the file you get back. Redaction also wipes the image pixels under the box, not just the text. Look over the result yourself, because OCR can miss a word that isn't clearly printed.
What if you want to change text, not hide it?
To fix a word or change a number, the simple route is to convert the file to Word with PDF to Word, edit it, and save it as a PDF again with Word to PDF. What exactly to hide on common documents like a payslip or an ID copy is covered in the guide to hiding personal details.