How to Redact a PDF (Permanently Remove Text)

You need to share a document, but a few things have to stay private — a name, an account number, a salary, a diagnosis, a home address. The obvious move is to drop a black rectangle over the text. The problem is that in most PDF tools, that rectangle is just a sticker on top of the page. The words underneath are still there. Anyone who receives the file can drag the box aside, delete it, or simply select and copy the "hidden" text right out of it. This is one of the most common ways confidential information leaks — and it has embarrassed law firms, courts, and governments who published "redacted" files that were nothing of the sort.

Real redaction has to do more than hide text — it has to destroy it. This guide shows you how to redact a PDF properly, in your browser, so the covered content is permanently removed and can't be recovered.

Step-by-step: redact a PDF properly

1. Open the Redact PDF tool and drag in your file (or tap to browse). It opens right on the page and never leaves your device.
2. The first page appears in the preview. Use the Prev and Next buttons to move to the page you need.
3. Drag across any sensitive text to cover it with a black redaction box. Draw as many boxes as you need, on as many pages as you need.
4. Got a box slightly wrong? Tap the small × on the corner of a box to remove it, or use "Clear boxes on this page" to start that page over.
5. When every sensitive area is covered, click Redact & download. Each marked page is flattened to an image with the boxes burned in, and the file saves to your device.
6. Open the downloaded PDF and confirm you can't select or copy any text under the black boxes — proof the content is really gone.

Why "overlay" redaction is a data-leak risk

When you draw a black shape in a typical PDF editor, you're adding an annotation or a filled rectangle on top of the existing page. The original text object stays exactly where it was in the file's structure. That means the "redacted" information can be exposed in several trivial ways:

• Select and copy. Highlighting the black area and pasting it into a text editor reveals the words underneath.
• Move or delete the box. The rectangle is a separate object; anyone can select and remove it.
• Search the text. A find-in-document search still matches the hidden words, because they're still indexed.
• Extract the raw content. Tools that pull text out of a PDF ignore the visual layer entirely and return everything.

This tool avoids all of that by taking a fundamentally different approach, described next.

What actually happens when you redact here

The distinctive — and important — thing about this tool is that a redacted page is flattened to an image. When you click download, every page you marked is re-rendered as a flat picture with your black boxes painted directly into the pixels. The original text and objects beneath each box are thrown away, not merely hidden. What's under the black is gone for good: there is no movable box, no selectable text, and nothing for an extraction tool to recover.

The honest trade-off is this: because a redacted page becomes an image, its text is no longer selectable or searchable, and that page is a little larger in file size. Pages you don't mark are copied through untouched and keep their crisp, selectable text. So only the pages that genuinely need redacting lose their text layer — which is exactly the price of making the sensitive information truly unrecoverable.

Tips and common pitfalls

• Cover generously. Draw boxes slightly larger than the text so no stray letters or descenders peek out at the edges.
• Don't forget hidden copies of the data. The same sensitive detail may appear in a header, footer, table of contents, or a later page. Check every page before you export.
• Redaction won't clean metadata. Names, authors, and other details can live in the document's properties. If that matters, also run the file through our PDF metadata viewer to see and strip that information.
• Keep the original private. The redaction is permanent by design, so save an untouched copy for your own records — and make sure you only ever share the redacted version.
• Redaction isn't encryption. If you also want to stop unauthorised people from opening the file at all, add a password afterwards — see how in our password-protect a PDF guide.