SantaPDFTools
Free · No Signup · 100% Browser-Based
Permanently Black Out Sensitive Text in a PDF
Draw black boxes over sensitive text or images before sharing a document. The tool permanently flattens those redactions into the page so the hidden content can't be recovered by selecting text underneath.
Why just drawing a box elsewhere isn't real redaction
A common mistake is covering sensitive text with a shape in a regular PDF viewer. The box sits visually on top, but the text is still there underneath, recoverable by anyone who selects it or deletes the shape. Real redaction has to remove the underlying content, not just hide it.
How this tool makes it permanent
After you draw your redaction boxes, the affected page gets rebuilt as a flattened image with the black boxes baked into the pixels. There's no separate text layer or shape to peel back afterward.
How to Use This Tool
- Upload the PDF containing sensitive information you need to permanently hide.
- Drag a box over any text, image, or region you want to black out — add as many boxes as needed across any page.
- Click Save Redacted PDF.
- The tool doesn't just draw a black box on top — it rebuilds each redacted page as a flattened image, permanently destroying the underlying content so it can't be selected, copied, or recovered.
Tips for the Best Results
- This is true redaction, not just visual covering — many free online tools only draw a black rectangle over text while leaving the original text still selectable and copyable underneath, which is a real security risk this tool specifically avoids.
- Double-check every redaction box before saving; once the file is flattened and downloaded, there's no way to recover what was underneath a redaction from that output file.
- Keep your original, un-redacted file stored securely and separately in case you need the full document again later.
Frequently Asked Questions
Is the content actually removed, not just covered visually?Yes, the page is rebuilt as a flattened image with the box baked in, unlike simply drawing a shape on top which someone could move or delete.
Can I redact the same area across every page?Redactions are drawn and saved per page. For a mark repeated on every page, Watermark PDF is a better fit.
Does redaction reduce searchability of the redacted page?That page becomes an image, so its text is no longer selectable. That's intentional, since it's what makes the redaction permanent.
What if I redact the wrong area by mistake?Use Clear Boxes on This Page before saving to remove marks and redraw them. Nothing is finalized until you save.
Is this real redaction, or just a black box drawn on top of the text?It's genuine redaction. The affected page is rebuilt as a flattened image, which permanently destroys the underlying text and data rather than just covering it visually.
Can the redacted content be recovered from the downloaded file?No. Because the page is flattened into an image, there's no selectable or extractable text left behind in the redacted areas.
Does this affect the whole page or just the boxed area?Only pages with at least one redaction box get flattened into an image; the rest of the document keeps its original text-based format.
← See all 62+ free tools on SantaPDFTools