Is my redacted PDF safe?
Upload a PDF you believe is redacted. We extract everything a stranger could copy out of it — locally, without uploading.
How to check whether a “redacted” PDF is actually safe
- Drop the PDF you believe is redacted — it is analyzed locally, never uploaded.
- Blackbar extracts everything a stranger could copy or search out of the file, page by page, plus the document metadata (title, author…).
- If hidden text shows up under your black bars, the redaction is fake — redact it properly with the redact tool.
FAQ
Why can text under a black bar still be copied?
Because the bar is just a rectangle drawn on top. The text object underneath is still part of the file, so copy, search and screen readers all read it. Court documents have leaked this way repeatedly.
The check found no extractable text — am I safe?
Mostly, but review visually too: scanned or photographed pages can still show sensitive content as pixels, which text extraction cannot see.
Is my file uploaded for the check?
No. The analysis runs entirely in your browser on this static site — there is no server that could receive your document.
怎么检测「已脱敏」的 PDF 是否真的安全
- 把你认为已脱敏的 PDF 拖进来——分析全程本地进行,不上传。
- Blackbar 会逐页提取陌生人能从文件里复制或搜索出的所有内容,外加文档元数据(标题、作者等)。
- 如果黑条下面还有可提取的文字,说明是假脱敏——去脱敏工具里重新处理。
常见问题
为什么黑条下面的文字还能被复制?
因为黑条只是画在上层的矩形,底下的文字对象仍在文件里,复制、搜索、屏幕朗读读到的都是它。法庭文件因此泄密的事故一再发生。
检测显示没有可提取文字,就绝对安全了吗?
基本安全,但请再目检一遍:扫描或拍照的页面可能以像素形式暴露敏感内容,文字提取看不到它们。
检测时文件会被上传吗?
不会。分析完全在你的浏览器里进行,本站是静态页面,没有能接收文件的服务器。