Black out sensitive areas and add text notes to a PDF — free and private.
Use this tool free →NilPDF Redact lets you permanently black out sensitive text, numbers, or images and add custom text notes directly on a PDF page — all rendered and applied locally in your browser. Draw a box over anything you want hidden, or click to drop a note, then download the edited PDF. Nothing is ever uploaded to a server.
Yes — completely free, unlimited use, no account required.
Your files never leave your device. All processing happens in your browser using WebAssembly (Pyodide). NilPDF has no server — there is nothing to upload to.
The black box is drawn permanently over the page, hiding the content visually. If the original PDF has a selectable text layer underneath, that text can still be extracted by copying it or parsing the file. For guaranteed removal, convert the redacted PDF to images first (use NilPDF's PDF to Images tool, then Images to PDF) before sharing it.