Blackout text in a PDF

Two black bars that look the same

Blacking out text is a description of how something should look. A bar, over some words, so nobody can read them. That is a completely reasonable thing to ask for and it is what this page does.

The catch is that two very different operations produce a bar you cannot tell apart by looking. One adds a black shape on top of the page. The words stay where they were, underneath the shape, in the file, and they come back the moment anyone thinks to look. The other takes the words out and gives you a picture of the page with the bar already in it. Side by side on screen, the two files are indistinguishable. Sent to somebody else, they are not remotely the same document.

You can tell which one you are holding in about as long as it takes to read this sentence. Drag across the blacked-out area as though you were selecting text, then paste it somewhere. If words appear, nothing was removed.

Why the drawn kind is what you usually get

Nearly every program that opens a PDF can draw a rectangle on one, because marking up a document is an ordinary thing to want. Those tools are annotation tools. An annotation is a note kept alongside the page — a highlight, an arrow, a comment, a filled shape — and the whole design of the feature is that it sits on top of the document without altering it. It is doing its job correctly when the text underneath survives.

So nothing has malfunctioned when you draw a black box and the words are still there. The mismatch is in the vocabulary. “Blackout” sounds permanent, the result looks permanent, and the operation that produced it was never meant to be anything of the kind. The word most software uses for actually removing the content is redaction, and it is a different feature that many products either put behind a paid tier or do not have at all.

If you want to see the difference proved rather than asserted, with a file you can run the check on yourself, that is on how to properly redact a PDF.

The apps you already have

On a Mac, Preview's markup toolbar draws a filled rectangle in about four clicks. On Windows 11, PDFs open in Edge, which has drawing tools that do the same. Adobe Reader and Foxit's free reader both offer comment tools that will put a black box anywhere you want one. Every one of those is the annotation kind, for the reason above: they are reader features, and readers annotate rather than edit.

Printing the annotated file back out to PDF gets suggested as a fix and it is not a dependable one. Whether the text layer survives that round trip depends on the printer driver doing it, and plenty of them preserve text faithfully, which is normally the behavior you want and here is exactly the behavior you do not. If you take that route, check the result before trusting it.

Paid tools do have the real thing. Acrobat's redaction feature removes text properly and is genuinely good at it. That is worth knowing if you already pay for it, and worth knowing you do not have to for one document.

What this page does with the box you draw

Drop the PDF in, drag a box over whatever should not be readable, and export. Each page you drew on comes back as an image with your bars part of it, and the file you download is assembled new rather than edited, so nothing from the original page rides along inside it. The bar looks the same as the one Preview would have drawn. What is behind it is not.

The cost of that is worth knowing up front: a page that becomes an image is a picture all the way across. Text elsewhere on the same page stops being selectable and searchable, screen readers lose it, and the file grows. Pages you never drew on are untouched and keep everything they had, so it pays to mark only the pages that need marking. After the export, the verify step lets you search the finished file for whatever you took out, which is the part where you stop taking anybody's word for it.

When a drawn bar is fine

Plenty of the time. Marking up a printout for your own use, hiding a figure in a draft while you work out what belongs there, covering something on a page nobody will ever open except you — anywhere the point is simply that a person looking at the screen cannot read a word. Annotation tools are good and there is no reason to avoid them.

The line is whether the file itself goes anywhere. The moment the PDF is what you hand over — emailed, uploaded to a portal, attached to a filing — a drawn bar stops being a decision about appearance and becomes a decision about who can read what. That is the case the tool above is built for.

Common questions

How do you black out text in a PDF?

Two different things get called this. Almost any PDF viewer will let you draw a filled black rectangle over the words, which changes how the page looks and leaves the text sitting underneath the shape. The other kind turns the page into an image with the bar baked into it, so the words stop being in the file at all. Both look identical on screen. The tool above does the second kind: drag a box over the words, export, and what you download has the text gone rather than hidden.

How do I black out text in a PDF for free, online?

Nothing here is charged for, gated behind a sign-up, capped per day or stamped on the way out. It is online in the sense that you loaded the page from the web, but the document itself never travels. Everything runs inside this tab, and once the tab has everything it needs the network is optional — unplug it before adding your file and the black bars and the export both happen anyway. Reaching a different page on the site is the one thing that still wants a connection. Tools answering this query tend to do one of two other things — send the document to a server, or hand you a drawing tool — and the difference between those and this is worth a minute before you pass the result to anybody.

How do I black out text in a PDF on a Mac?

Preview can draw the rectangle: open the markup toolbar, pick the shapes tool, drop a rectangle over the words and fill it black. That is a drawing, though, and the text stays in the file beneath it, where selecting the area and copying brings it back. If the file is going to somebody else, use something that removes the text instead — this page works in Safari or Chrome on a Mac and needs nothing installed.

How do I black out text in a PDF on Windows 11?

Windows 11 opens PDFs in Edge by default, and Edge has drawing tools that will put a black shape over anything you like. Same catch as everywhere else: the shape is added to the page rather than replacing what is under it, so the words are still in the document. This page runs in Edge and does the removing kind, which is the version you want if the file is leaving your machine.

How do I black out text in a PDF in Adobe Reader or Foxit?

Both have comment and markup tools that will draw a black box, and in both cases you are annotating the page rather than editing it — the text underneath survives. Adobe Reader is the free product and has no redaction feature; the paid Acrobat does, and it genuinely removes the text rather than covering it. Foxit splits the same way between its free reader and its paid editor. If you would rather not pay for a one-off job, this page removes the text in the browser at no cost.