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OS Authority

Black out text in a PDF for good

Hide names, account numbers, addresses or anything else before you share a PDF. The text under each black box is removed, not just covered, and your file never leaves your device.

Your PDF is processed on this device and never uploaded. We don't see, store or log your files.

How it works

  1. Tap Choose file and pick your PDF.
  2. Type a word or number and tap Find and black out to cover every match, or tap the page to draw boxes.
  3. Check each page; move, resize or remove boxes as needed.
  4. Tap Redact PDF, then Download or Share the result.

Why a black box isn't always enough

Many editors draw a black rectangle on top of the page. The text is still underneath: anyone can select it, copy it or search for it. Here, every page with a box is redrawn as an image with the boxes painted in, so the text, pictures and drawings under them are gone.

What changes in the PDF

Redacted pages become images at 200 DPI, sharp enough to read and print, but their text can no longer be selected or searched. Pages without boxes stay exactly as they were. The document's hidden details (author, title, dates), its bookmarks, the hidden copy of the text used by screen readers, and form fields on redacted pages are removed too, because they can repeat what you blacked out.

Finding every match

Find and black out searches every page for the word or number you type, ignoring capitals, and boxes each match. Check the result page by page: scanned pages have no text to search, so draw boxes there yourself.

Keep the original

Redaction can't be undone in the new file. Keep your original PDF, and send only the redacted copy.

Frequently asked questions

Can the hidden text be recovered?

Not from this PDF. The redacted pages are images, and the text that was under the boxes isn't in the file any more.

Why is my redacted PDF larger?

Redacted pages are stored as images, which usually take more space than text. Compress PDF can make the file smaller.

Does it work on scanned documents?

Yes, with boxes you draw. Find and black out needs real text, which scanned pages don't have.

Is my PDF uploaded?

No. Everything happens in your browser on your own device.

Last reviewed: October 2, 2026

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