Redact PDF
Draw a box over a name, an account number or anything else you need to hide, and it is deleted from the file — not covered up. Every result is read back and checked before you can download it, so what you hid stays hidden.
- 1Add a PDF
- 2Mark what to hide
- 3Download a PDF with it truly removed
Your files are processed on this device and never uploaded.
How to use Redact PDF
- Choose a PDF. Every page is shown so you can see what to hide.
- Drag a box over each thing you want removed. Click × on a box to take it away again.
- Press Redact. The marked content is deleted, black boxes are drawn in its place, and the new file is read back to confirm the content is really gone.
- Download the redacted PDF once it has passed that check.
About this tool
A black box is not redaction. In a PDF, the text you see and the shapes drawn over it are separate layers. When most tools “redact”, they add a black rectangle on top and leave the words underneath exactly where they were. The page looks blacked out, but select the area and press copy, or open the file in another program, and the hidden text comes straight back. Court filings and official reports have been published this way, with names and figures that were supposed to be hidden readable by anyone who tried.
This tool deletes the content itself. Each page’s drawing instructions are rewritten so the letters inside your boxes are removed, along with any shapes that sit entirely inside a box. Only then is the black box drawn, over an area where nothing is left. The text around it stays exactly where it was and can still be selected.
Every file is checked before you get it. The finished PDF is opened again and all of its text is read back, the same way a reader or a search engine would. For each page you redacted, three things must hold: the words you hid are gone, nothing at all remains inside a box, and everything outside the boxes is unchanged. If any page fails, you are told which one and no file is offered. A file that only looks redacted is worse than none.
Some things cannot be cut out letter by letter: a scanned page, a photo of a signature, or text in an unusual font. When a box covers something like that, the page is turned into a 200 DPI image with the black box burned in, and you are told plainly which page that happened to and why. Text elsewhere on that page can no longer be selected; every other page is left as it was.
A PDF also carries information that is not on any page. The title and author fields often still say what a document was before it was redacted, and bookmarks, attachments, page thumbnails, comments and form fields can repeat the very details you removed. The title, author and other document details are removed, as are bookmarks, attachments and page thumbnails. Comments, links and form fields are removed from every page you redact. And because the tool looks for the words you removed on other pages, it tells you if a name you hid on page 1 is still sitting on page 7.
All of this happens in your browser, on your own device. The document is never uploaded, which matters when the whole point is keeping something private.
Frequently asked questions
Is this real redaction, or just a black box?
Klonum’s Redact PDF does real redaction: the text, shapes and images under each box are deleted from the file, then a black box is drawn where they were. The result is read back and checked before you can download it, so the hidden text cannot be selected, searched or copied out.
Why was one of my pages turned into an image?
Redact PDF turns a page into an image when a box covers something that cannot be removed letter by letter — usually a scan, a photo or a signature image. The only safe way to remove part of a picture is to flatten the page into a new picture with the box burned in. You are told which pages this happened to; text on them is no longer selectable.
What if a name I redacted appears somewhere else?
If a name you redacted appears somewhere else, Redact PDF lists the other pages where it still appears so you can mark those too, because redaction only removes what you mark.
Is my document uploaded anywhere?
No, Redact PDF does not upload your document: the pages are drawn, edited and checked by your browser on your own device. Nothing is sent to a server, which matters when the whole point is keeping something private.