Mark what has to go. Every page is rebuilt as an image, so the words are destroyed rather than covered — and the finished file is read back and searched before you are offered a download.
Self-check
Nothing checked yet
No, and that is the mistake this tool exists to avoid. A rectangle drawn on top is a separate object; the words underneath stay in the file and can be selected, searched and copied out. This tool converts each page to an image and rebuilds the document from those images, so the text is gone rather than hidden.
The finished file is opened again, as a stranger receiving it would open it. Its text is extracted and every phrase you marked is searched for. The download appears only if there are zero matches, no extractable text at all, no annotations, form fields or attachments left, and every mark is solid black in the finished page image.
You get no file. The result panel says which check failed and why, and nothing is offered for download, because a redaction that cannot be proved is worse than none — it is one you would have sent.
No. There is no server to send it to: this site is static files, and the work runs in your browser. You can confirm it by opening your browser's network panel, or by disconnecting from the internet after the page has loaded — the tool keeps working.
Because it is now made of page images. That is the trade: a redaction you can rely on costs you the text layer and some file size. If you need selectable text elsewhere in the document, keep your original — this file is the one that is safe to send.
Yes. The new document is built from scratch, so document metadata, annotations, form fields, attachments and any document-level scripts are not carried over. The finished file has no title, author, producer or timestamps.