⬛ Redact PDF (Flatten & Burn In)
Draw boxes over what must go, and the tool re-renders every page as a flat image with the boxes burned in — so the hidden text doesn't exist in the output, rather than hiding under a rectangle.
Safe by construction: instead of hiding text under boxes (the failure mode behind most redaction scandals), every page is re-rendered as a flat image with the boxes burned in — the underlying text, fonts, metadata and attachments simply don't exist in the output. Trade-off: the result is no longer searchable or selectable (like a scan), and it needs OCR to become accessible again. Verify any redaction with the redaction checker.
How the redact pdf (flatten & burn in) works
The tool renders each page with the pdf.js engine, you draw black rectangles over anything to remove (click and drag; boxes apply per page; undo as needed), and on export every page is re-rendered as a flat image with your boxes painted in before the image is written to a brand-new PDF. Because the output pages are pixels, not the original content streams, the sensitive text, fonts, metadata and attachments of the source simply do not exist in the result — there is nothing to un-hide. This is the same "print it and scan it" logic that forensic guidance recommends, done digitally at 144 DPI.
The deliberate trade-off: a rasterized PDF is no longer searchable or selectable, and its file size reflects the page images — that's the price of redaction that cannot be reversed by deleting an annotation. For documents that must remain accessible, run OCR on the redacted output afterwards (the text you removed stays gone — OCR can only read what's visible). Belt and braces: run the result through the redaction checker; it should report zero extractable characters.
Frequently asked questions
Why flatten pages to images instead of just adding black boxes?
Because a drawn box leaves the text underneath intact and extractable — the failure behind most public redaction scandals. Flattening re-creates each page as pixels with the box burned in: the content beneath was never copied into the new file, so no editor, script or copy-paste can recover it.
Is the redaction really irreversible?
Yes, for the file this tool produces: the output contains only page images rendered with your boxes already applied. The original text, fonts, metadata and attachments are not carried over in any form. (Keep the original somewhere safe if you need it — this is a one-way door for the output file.)
What quality are the flattened pages?
Pages render at twice their nominal size (≈144 DPI), which keeps ordinary documents crisp on screen and in print. The result behaves like a good scan: readable, printable, but not text-selectable.
How do I redact across multiple pages?
Navigate with Prev/Next and draw boxes on each page that needs them — the counter shows total boxes and per-page boxes. Export flattens every page of the document, including ones without boxes.
Is my document uploaded?
No — rendering, drawing and rebuilding all happen in your browser, and the tool works offline. Documents being redacted are exactly the files that should never touch a third-party server.