PDF Redaction Leak Checker
Upload a PDF that's already been "redacted" somewhere - by this site's own Redact PDF tool, or any other tool or editor - and check whether the text under those black boxes was actually removed, or is just covered up and still there to copy-paste or extract.
Perguntas frequentes
Why would a redacted PDF still leak text?
Many redaction methods only draw an opaque black shape on top of the original content, as an annotation or a layer, without deleting the text underneath. The page looks redacted, but the original text is still part of the file - anyone can select it, copy it, or extract it with a script, even though it's not visible on screen. This is a well-documented, recurring cause of real-world data leaks.
How does this tool check for that?
It does two independent passes on every page: it extracts the real, selectable text and exactly where it sits on the page, and separately scans the rendered page image for solid black or very dark rectangular regions. If any extracted text sits underneath one of those regions, it's flagged as a leak and quoted so you can see exactly what's exposed.
What if it finds no black boxes at all?
Then there's nothing for this tool to check - it only looks for text hiding under a solid dark box shape. If you expected to see redaction marks and don't, double check you uploaded the redacted version of the file, not the original.
Does a clean result guarantee the PDF is safe to share?
It's a strong, genuinely useful check for the most common failure mode (text left under a cover box), but it isn't a substitute for a full manual review. It won't catch sensitive content in image form (a scanned photo of sensitive text), metadata left in the file's properties, or hidden layers/comments unrelated to a black box. When in doubt, use a tool that flattens the whole page to an image (like this site's Redact PDF tool) rather than relying on a cover shape.
Is my PDF uploaded anywhere?
No. The file is rendered and analyzed entirely in your browser using JavaScript - it's never sent to a server.