How to redact a PDF without Adobe, and check the text is really gone
Before a contract, a court exhibit or a record with personal details goes out, some of it must go. This guide shows how to black it out for good, in your browser, without uploading the file anywhere.
Why a black box is not enough
A black rectangle, a highlight or a comment drawn over text in a PDF only covers it. The text is still in the file: anyone who receives it can select it, search for it, copy it or move the box away. Court filings and public releases have exposed confidential details exactly this way.
Text blacked out in Word before exporting to PDF can survive in the same way, depending on how it was done.
How kami blacks out a page
Every page that has a box is replaced by a picture of itself with the boxes already painted in. No text is left on that page to select, search or copy. Pages without a box keep their text.
The whole job runs inside your browser. The file is never sent to us or to anyone else.
Steps
- Open Black out (redact) and drop your PDF. Its pages appear at reading size.
- Type the names or numbers to remove in "Words to black out, one per line". Every occurrence on every page gets a box.
- Drag boxes over anything the search cannot find, such as signatures, handwriting or pictures. Click a box to remove it.
- Choose the quality of the blacked-out pages: Standard for screens, High for printing.
- Press Run and download the result.
Check that it worked
- Open the downloaded file and search for each word you removed (Ctrl+F or Cmd+F). There should be no match.
- Try to select text on a blacked-out page. Nothing should highlight.
- Words that were not found are listed after the run. They were not blacked out: draw boxes over them and run again.
Things to know
- Scanned pages have no text, so the word search cannot find anything on them. Draw boxes instead.
- Blacked-out pages become pictures, so their remaining text cannot be searched. Run Text recognition (OCR) on the result if the filing needs to be searchable.
- Names can also hide in the file's properties. Run Remove author info too, and give the file a neutral name.
Questions and answers
Can someone recover the blacked-out text from the file?
Not from the file kami makes: a blacked-out page is a picture with the box painted in, and the original text is not in it. Your original file is not changed, so keep it safe separately.
Is my PDF uploaded?
No. Opening, searching, blacking out and saving all happen in your browser.
Is this a Pro feature?
Yes. You can try it once for free, then with a 7-day pass or a lifetime key. No subscription.
Last updated: 2026-09-14