How to black out text in a PDF (so it's actually gone)

You've got a PDF to send, and there's something in it the other person shouldn't see: an account number, a home address, a name, a salary. So you want to black out text in the PDF before it goes. Here's the catch most people find out too late: a black box drawn on top usually leaves the words sitting right there in the file, where anyone can copy them out.

This post shows how to black out text in Edit PDF so the words are actually gone, then how to check your redaction in about ten seconds before you hit send.

Black box vs. redaction: what's the difference?

Blacking out is how the page looks. Redacting is what's in the file. They sound like the same thing, and that's exactly how private details leak.

When you draw a black rectangle, a thick pen stroke or a black highlight in almost any PDF app, you're adding a layer on top of the page. The text underneath doesn't go anywhere. Someone who gets the file can often:

• select the hidden words with their cursor and copy them
• find them with a search
• click the box and drag it out of the way

People have leaked court filings and government documents this way, with every line looking perfectly blacked out on screen. So the black bar is the part people see. The part that protects you is taking the words out.

How to redact a PDF, step by step

In Edit PDF it's two jobs: delete the words, then cover the spot so readers can see something was removed. You need a PDF with real text in it for the first part (if you can select the words with your cursor, you're fine). Scans are different, and they get their own section below.

Delete the words

1. Open Edit PDF and choose your PDF.
2. Click Edit Text in the toolbar. Blue boxes appear around the blocks of text.
3. Click into the block with the private words, select them, and delete them, the way you would in a document.

Paint the black bar

4. Click Draw. The pen starts out black, the first color in the row.
5. Open the line thickness menu and pick the thickest line (20 points).
6. Zoom in and paint over the spot, back and forth, until it's a solid bar. Go a little past the edges.
7. Click Download, then PDF.

When you've drawn on the page, the download menu also shows Lock annotations, ticked by default. Leave it ticked. It bakes your black bar into the page, so nobody can click it and delete it in another PDF reader.

Made a stray mark? The undo arrow takes back the last stroke. Editing is free whether or not you're signed in; downloading the finished file takes a free account.

Why bother with the bar at all, if the words are already gone? Because a gap with no mark looks like a mistake. A black bar tells whoever reads the page that something was taken out on purpose.

Check your redaction before you send it

This is the step that matters most, and almost every guide skips it. Don't trust how the page looks. Open the PDF you just downloaded (not the one in the editor) and try to get the words back:

1. Search for them. Press Ctrl+F (Cmd+F on a Mac) and type the word or number you removed. Try part of it too, like the last four digits.
2. Try to select the spot. Drag your cursor across the black bar. If text highlights under it, something's still there.
3. Copy and paste. Select the whole line around the bar, copy it, and paste it into a blank note or email. Read what comes out.

If anything turns up, it isn't redacted. Go back to Edit PDF, delete what you missed with Edit Text, download again, and run the check again.

Redacting a scanned PDF or an image

A scanned PDF is a photo of a page. There's no text in it, so Edit Text has nothing to grab, and a black bar from the Draw pen covers the words without taking them out. Even with Lock annotations ticked, the original picture is still in the file under your bar.

For a quick visual cover on something low stakes, the pen is fine. For anything you'd hate to see leak, the safest route for a scan is to black it out on paper: cover the words with opaque tape or a strip of paper, then scan the page again. Words that never reach the scanner can't turn up in the file.

Don't forget the hidden places

The page isn't the only place a PDF keeps information. Before you send, check:

• The file name. "Smith_divorce_settlement_final.pdf" says plenty on its own. Rename it.
• Document properties. PDFs carry a title, author, subject and keywords that most people never look at. Open Edit PDF Metadata to see them, and change or clear anything you don't want to share, like the author's name.
• Comments and sticky notes. Notes someone added while reviewing ride along with the file.
• Form fields. A filled-in field can hold the very number you blacked out elsewhere on the page.
• Bookmarks. If the PDF has a sidebar of bookmarks, their titles can name what you removed.

What about Acrobat?

Adobe has a dedicated Redact tool, and it's the real thing: it removes the content you mark, can find a word or a pattern (like phone numbers) everywhere in the file at once, and can strip out hidden information. It's part of Acrobat Pro, the paid plan, which is why people hunting for it in the free Acrobat Reader don't find it.

Here's where we stand, honestly: Edit PDF doesn't have a one-click Redact button or find-and-redact. If you're blacking out the same name across a 300-page legal file, a dedicated redaction tool will save you hours. If it's a few lines on a bank statement or a form, deleting them with Edit Text and adding a black bar does the job, and the check above tells you it worked.

If you want to fix a typo or cover something in white instead, our guide to whiting out a PDF walks through that. For what needs a free account and how big a file can be, see Edit PDF in What Each Tool Does.