A free, private PDF redactor that lets you permanently black out sensitive information — names, addresses, account numbers, signatures, salary figures — before you share a document. You upload a PDF, drag black boxes over anything that should be hidden, and export a new file where that content is genuinely gone, not merely covered. Everything happens inside your browser, so confidential paperwork never touches a server.
How it works
Most “redaction” you see online is cosmetic: a tool draws a rectangle on top of the page while the underlying text stays intact in the file. Open that PDF in a different reader and the text can be selected, copied, or the rectangle dragged aside — the secret was never removed. This tool takes a stricter approach.
When you upload a PDF it is rendered page by page with pdfjs-dist, the same
engine that powers in-browser PDF viewers. You draw your redaction boxes directly
on the rendered page; each box is stored in PDF-point coordinates so it stays
accurate whatever zoom you use. On export, every page is re-rasterised at your
chosen resolution, the black boxes are painted onto that bitmap, and a fresh PDF
is rebuilt from the flattened images with pdf-lib. Because the original text and
vector layer is discarded, the redacted areas cannot be selected, copied, or
recovered from the output. The trade-off is that the exported pages become images,
so keep your original if you still need editable text.
You can mix redaction styles per document — solid black, a labelled “REDACTED” block, or a white outlined box — and choose an export DPI to balance sharpness against file size. There is a one-click “header band” helper for the common case of blanking a running header or footer that carries a name or reference number.
Example
You have a signed tenancy agreement to send to a guarantor, but you must hide your
bank details and date of birth. Upload the PDF, drag a box over the sort code and
account number on page two, drag another over your date of birth on page one, and
optionally add a header band to cover the document reference. Pick 150 dpi and
the solid black style, click Export redacted PDF, and download
agreement-redacted.pdf. The guarantor receives a clean copy; the hidden fields
are flattened into the page image and can never be lifted back out.
Every step runs locally. No upload, no account, no watermark on the output — the redaction is real and the file stays on your device.