UtilForge
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Black out a PDF file, then check it worked.

Free checkNo sign-upsNo trackingKeeps working with the internet off

To redact a document is to black out parts of it so nobody can read them. Most redaction tools take the words out but leave the spacing, and researchers have shown that the spacing alone can reveal the names underneath. This tool rebuilds each page as a picture, so no text and no spacing are left to measure. It then opens its own result, checks it, and gives you a report.

The short answer. To redact a document is to black out parts of it so nobody can read them. This tool rebuilds each page as a picture, so no text or spacing is left underneath, then opens its own result, checks it and gives you a report. All of it happens on your own computer.

How it works, in four steps

  1. Paste or chooseChoose a PDF (Portable Document Format) file and mark what must be blacked out.
  2. The check runs on your own phone or computerWhat you add stays on your device, and the page keeps working with the internet off.
  3. Read what it found and what to do nextSave the redacted copy. The page checks its own output before handing it over.
  4. What this check cannot doThe finished pages are pictures, so they cannot be searched or read aloud by screen readers.

1. Open a PDF file

or drag one here

Your file is not transmitted. Everything happens in this tab, on this device. To test it yourself, load this page, turn off your wifi, then open a PDF (Portable Document Format) file. It still works.

What this does and does not do

  • The new PDF file is made of page pictures. You cannot search it or select its text, and screen readers cannot read it. If you must produce documents that people using screen readers can read, this matters.
  • Optical character recognition (software that reads text from a picture) can still be run on whatever stays visible, as with a photocopy.
  • The tool removes the text. It does not hide the fact that something was removed.
  • Encrypted and password-protected PDF files are not opened.
  • Large documents may use up this tab’s memory. Progress is shown page by page.
  • This tool does not make you compliant with anything. It removes content from a file.
  • Digital signatures do not survive redaction. They are removed, and the report says so.

How Redaction Studio works: how a page becomes a picture, why that stops the spacing method from working, what each box style does, and what this tool does not do.

The wifi test

  1. Load this page.
  2. Turn off your wifi.
  3. Open a PDF file and redact it. It still works.

Questions people ask

Who made this?

UtilForge makes it. UtilForge is a website of free cybersecurity tools. The About page explains why the tools were made, and the Contact page is the way to reach us.

Is this a scam site?

You do not have to take our word for it, because you can check. This page does not ask for payment, a sign-in or card details. It is set so that your browser stops the page sending anything off your phone or computer, and you can test that: let the page finish loading, switch the internet off, then use it. It keeps working, because it has nowhere to send anything. If you are still unsure about any website, do not type anything private into it. The full version is a separate, optional purchase, sold on the Release Check page, and the page works without it.

What happens when I close the page?

The file you opened and the redacted copy held on the page are gone. It saves nothing in your browser and puts nothing in the web address of the page. Your original file is never changed. A redacted PDF files or report that you downloaded stays in your downloads folder until you delete it, so keep track of which one is the redacted copy.

Does it cost anything, and do I need to sign in?

You can start straight away. The free version redacts documents of up to 3 pages. The full version removes that limit and costs $29, one payment, sold on the Release Check page.

How does Redaction Studio remove content from a PDF file?

It rebuilds each page as an image, so there is no spacing, no text layer and nothing left to measure. Then it re-opens its own output and checks it before you get a file. If any check fails, no file is produced.

Will the finished PDF file be searchable?

No. The output is an image-based PDF file. It is not searchable or selectable, and screen readers cannot read it. If you are required to produce accessible documents, this matters.

What are the three box styles?

Uniform blocks make every box the same width, so the length of what was removed is not revealed; this is the safest default. Whole line covers the entire line, which is the safest and most disruptive. Exact fit matches what you marked, which is convenient but leaks the length of the removed text.

What does Redaction Studio not do?

It does not make you compliant with anything; it removes content from a file. Digital signatures do not survive redaction, and the report says so. It does not open encrypted or password-protected PDF files. Anyone can still run optical character recognition on what remains visible, exactly as with a photocopy.

Why does the spacing of the words matter?

The page explains that most redaction tools remove the words but leave the spacing, and that researchers have shown the spacing alone can reveal the names underneath. Rebuilding each page as an image removes the spacing too.

Did this check help you?

Tell UtilForge what worked and what did not. Each button opens an email to lindsay@utilforge.org that you write and send yourself. UtilForge will only quote your words on this site if you say it may, and then with your first name and country only.

Yes, it helpedSomething was missing

The whole method in one book. “How to Become Safer Online” is a free large-print guide to the five steps most scams follow, and what to do if money or details have already gone. Read or print the free book.