How to redact a PDF
- Add your PDF. Drag it onto the box or click to browse. The tool reads it on your device and shows the total page count.
- Draw boxes over what needs hiding. Click and drag on the page preview to draw a black box. Draw as many as you need on that page.
- Move to the next page. Use Prev and Next to work through the document. Use Undo last box or Clear this page if you make a mistake.
- Redact and download. Press Redact & download. Every page, marked or not, is rebuilt as a flattened image and a new PDF downloads instantly.
Real redaction versus a black box on top
A lot of "redact PDF" tools online just draw a black rectangle on top of the page and call it done. The text underneath is still there. It can be selected, copied, or pulled out with a PDF text extractor in a few seconds, and this has caused real, public leaks: court filings, government documents and corporate reports have all gone out with "redacted" names and numbers that were trivially recoverable, because the box was cosmetic. That is a fake redaction, and it is arguably worse than no redaction at all, because it looks safe.
This tool does not do that. When you press Redact & download, every page of your PDF, including pages with no boxes on them, is rendered to a high-resolution image using the same rendering engine your browser uses to display the file. Your black boxes are drawn directly onto that image's pixels. Then an entirely new PDF is assembled from those page images, one image per page, using pdf-lib. The original text objects, fonts and vector paths from the source file never enter the new document. There is no hidden layer to peel back, because the layer that used to hold the real text simply is not in the output.
When to use it
Reach for this before sharing anything where a mistake would be expensive to unwind: a lease or contract with a Social Security number, a medical record with a patient's details, a bank statement, a screenshot with an account number or email address visible in the corner, or a legal filing that needs a name blacked out before it goes public. Anywhere a cosmetic overlay would be a liability, a flattened, image-based PDF removes the risk entirely.
The tradeoff: no more selectable text
Guaranteeing that redacted content cannot be recovered means the whole page has to become a picture of the page, not the original text and layout. So after redacting, nobody can select, copy or search text anywhere in the file, not just in the boxed areas. The page looks the same and prints the same, but it behaves like a scanned document rather than a live PDF. If you need a searchable copy for your own records, keep the original file before you redact, since the source and the redacted output serve different purposes.
Frequently asked questions
Is this actually secure, or just a black box on top?
It is real redaction. Every page is rendered to an image with the black boxes burned into the pixels, then a brand new PDF is built from those images only. There is nothing to select or extract underneath a redacted area.
Can I get the covered text back afterward?
No. Once a box is applied and the file is rebuilt, the pixels underneath the black areas are gone from the output. Keep your original file if you need the unredacted version later.
Is my file uploaded anywhere?
No. The PDF is opened, marked and rebuilt entirely in your browser using JavaScript. Nothing leaves your device.
Why can I no longer select or search the text after redacting?
Because the whole page becomes a flattened image, not just the redacted area. That is the tradeoff for guaranteeing nothing can be recovered.
Related: watermark a PDF · delete PDF pages before sharing.