Redact PDF documents in your browser. Draw black boxes over any sensitive text or images on any page, and download a clean, redacted PDF.
Yes. You can black out sensitive information in your PDF right here online for free — no account, email, or credit card required. Sign up only if you want higher limits, larger files, or API access.
Yes. Uploads travel over an encrypted HTTPS connection, are processed on our servers, and are automatically deleted within a few hours. We never share or sell your documents.
No. PDF4 works entirely in your web browser, so there is nothing to download or install. It runs on Windows, macOS, Linux, Android, and iOS.
PDF4 draws an opaque black box over the selected area and flattens it into the page image, hiding the content visually. For the highest-assurance legal redaction of the underlying text layer, also run the result through Flatten PDF or convert to images.