How to Redact PDF Online Free: Black Out Text, Truly Remove It, and Check Nothing Leaks
An account number on a bank statement. A client’s name in a court filing. When you redact a PDF, the goal is not to make the words harder to see; it is to make them gone. Plenty of files have been “redacted” with a drawn rectangle, only for the hidden text to be copied straight out from underneath. This guide shows how to black out text in a PDF so the words are deleted from the file, how to find every copy of a name at once, how to prove the result is clean, and — just as plainly — which kinds of content a box cannot remove and where to go for those.
1. What PDF Redaction Is, and Why a Black Box Is Not Enough
PDF redaction means permanently removing information from a document before someone else sees it. On paper that was a marker pen. In a PDF it is two separate jobs, and most redaction failure PDF stories come from doing only the first one.
Covering
A rectangle is drawn on top of the words. The page looks redacted, but the text is still underneath: search finds it and copy and paste lifts it out.
Removing
The characters under the box are deleted from the page, then the box is painted where they were. Nothing is left to search, copy or uncover. This is true redaction, and the default here.
If the text must be unreadable to the next person who opens the file, you need a PDF redaction tool that removes it, and a way to check that it did.
2. How to Redact a PDF Online Free in Four Steps
Here is how to redact a PDF with the tool at the top of this page. It is a free PDF redactor with no sign-up: no account, no trial, no daily limit, and no need for paid desktop software.
- Choose the PDF. Drop it onto the panel or click to browse, one file at a time. A password-protected file must be unlocked first; the PDF unlocker removes it if you know the password.
- Mark the regions. Drag on the page preview to draw a box over each thing to hide, and use the page selector to move between pages. A status line counts your regions.
- Pick the box colour. Black is the default. Choose white if you want to white out text in a PDF so the gap blends into the page; the text underneath is removed either way.
- Apply and download. Press Apply redaction. You see how many characters were permanently removed, and the file downloads as -redacted.pdf, leaving your original untouched.
Remove underlying text (true redaction) is ticked from the start. Untick it only for a cover-only box you can take off later; for anything leaving your hands, leave it on.
3. How to Redact All Instances of a Word in a PDF
Drawing every box by hand is how names get missed. Type the name into Find text and press Mark all matches: a box is placed over every match on every page, and you are told how many were found. Then page through and look at each one before you apply, because a match is exactly the text you typed and nothing more.
The search is literal and ignores case, so “smith” finds “SMITH”. It does not match patterns, so it cannot find “every email address”; search for each specific value instead. A phrase stored in separate pieces may be missed, so try its single words too. No matches usually means the words are part of an image or were converted to shapes.
4. What Is Removed, What Is Covered, What Stays
Knowing how to remove sensitive information from a PDF starts with knowing what happens under each box.
- Text is deleted. Every character overlapping a box is removed, with its space kept so the line does not shift. The file is written fresh, so the old words are not hiding in an earlier saved version inside it.
- Links and comments are removed wherever they overlap a box.
- Images are covered, not erased. A photo, signature image or scanned page under a box is painted over, but its pixels remain in the file. For a scanned document, convert the pages with PDF to JPG, paint over the details with a black box in Image Blur, which replaces the pixels in the exported image, and rebuild the file with Image to PDF. To make scanned words findable first, run PDF OCR.
- Form fields are a special case. Values outside your boxes are kept, and some text in reusable page parts is only covered. Bake fields into the page with the PDF flattener before redacting.
- Metadata, bookmarks and attachments stay. The author, title, bookmark names and any attached files come through unchanged. Bookmark titles can be renamed with the bookmark editor; check document properties yourself before sending.
If a whole page should go rather than be blacked out, the page remover deletes it outright. Boxes here are always solid colour, with no blur or pixelate effect; if you want a blurred look, export the page as an image and use the Image Blur tool mentioned above. Several PDFs need redacting? The tool takes one file at a time, so work through them in turn and run the checks below on each.
5. How to Check If a PDF Is Properly Redacted
If you have ever found redacted text still visible when copied, or a black box PDF text still searchable with a simple find, you have seen a cover-only redaction. This tool checks its own work: with your search term still in the box and true redaction on, the finished file is re-read and you get either Verified: the search text no longer appears or a warning to mark the remaining areas. That check covers the search term only, not areas you boxed by hand, so test those yourself.
Then run three checks of your own on the downloaded copy:
- Search. Press Ctrl+F (Cmd+F on a Mac) in any PDF reader and search each redacted word. It should find nothing.
- Copy and paste. Drag-select across a black box, copy, and paste into a plain text editor. You should get blank space, not the hidden words.
- Select all. Press Ctrl+A, copy, paste, and read the result for anything you meant to remove.
Can a redacted PDF be unredacted? Text removed with true redaction on cannot be recovered from the new file, because it is no longer in it. A cover-only box can be lifted off, and an image under a box can be extracted, so scanned pages need the image route in section 4.
To see every change, open both versions in PDF Compare.
6. Bank Statements, Legal Files, Medical Records and FOIA
The same four steps cover very different jobs:
- Redact bank statement PDF files. A landlord wants proof of income, not your account number. Search the number to mark each copy, then box transactions by hand.
- Redact names from legal documents (PDF). For discovery or a public filing, search each party’s name, review every match, and run the three checks above.
- Redact medical records PDF files for HIPAA. The HHS de-identification guidance lists which patient identifiers count. Scanned charts need the image route in section 4.
- Redact PDF files for a FOIA request. Records officers removing exempt passages before release can find the rules and exemptions at FOIA.gov; this tool handles the removal itself.
- Redact resume PDF personal information, such as your home address and phone number, before posting it: a white box keeps the layout clean.
- Anonymize a PDF document for research or a case study by searching each name, place and ID in turn.
It works the same when you redact a PDF on a Mac or redact a PDF on a Chromebook: choose the file, draw, apply. On a Mac, open this page in Safari or Chrome and you can redact without buying paid PDF software.
7. Why Cortexis Is the Best Free PDF Redaction Tool
Many pages offer to blackout PDF online or censor PDF online. Few say what happens to the text under the box, and fewer check the result.
True redaction by default
Text under every box is deleted from the file, not just hidden, and overlapping links and comments are removed with it.
Verified, not hoped
The finished file is re-read for your search term, and you are told plainly whether it is gone or still appears elsewhere.
Find and mark every match
Type a name or number once and every copy on every page is boxed for you to review.
Your documents stay private
Files are never stored on our servers and nothing is retained after your session.
Nothing is used for training
Your statements, filings and records are never used for training.
Free, no sign-up, honest limits
No account, trial or daily cap. What the tool cannot remove is listed on this page, with the tool that can.
It sits alongside the rest of our free document tools. Want the redacted copy locked before you send it? Add a password with the PDF password protector.
8. Frequently Asked Questions (FAQ)
How do I redact a PDF online for free?
Choose the PDF in the tool above, drag boxes over what you want hidden, and press Apply redaction. The file downloads as a new copy ending in -redacted.pdf, with no account or daily limit.
Is the text actually removed, or just covered?
With Remove underlying text left ticked, which is the default, every character under a box is deleted from the file before the box is painted. Links and comments overlapping the box are removed too. Unticking the option gives a cover-only box that can be taken off later.
Why can I still copy or search text after blacking it out elsewhere?
Because a drawn rectangle only covers the words; the text is still in the file underneath. Redact the file again here with true redaction on, then confirm with a search and a copy and paste test.
Why is my PDF redaction not working?
If the text can still be searched or copied, the box only covered it: redact again here with Remove underlying text ticked. If Find text says no matches, the words are part of an image or were turned into shapes, so draw the box by hand or use the scanned-page route. If the file is refused, it is encrypted and needs unlocking first; if a phrase is missed, search its single words.
How do I redact a PDF without paid PDF software?
Use the tool at the top of this page. It is free with no account or trial: choose the PDF, draw boxes or mark every match of a word, and apply. The text under each box is deleted from the file, the same true redaction paid editors offer.
Can I redact every mention of a name at once?
Yes. Type it into Find text and press Mark all matches to box every exact match on every page, ignoring case. Review each page before applying, and search for single words too, since a phrase stored in pieces can be missed.
Can it find emails, phone numbers or card numbers automatically?
No. The search is exact text only, with no pattern matching. Search for each specific value you need hidden, or draw boxes over them by hand.
Does it work on scanned PDFs?
A scanned page is an image, so a box covers it but the pixels stay in the file. Convert the pages with PDF to JPG, black out the details with Image Blur, and rebuild with Image to PDF. PDF OCR can make scanned text searchable first.
Does redacting remove the author name and other metadata?
No. Document properties, bookmarks and attachments are kept as they are. Bookmark titles can be changed with the bookmark editor, and you should check the file properties before sharing.
Can I redact a password-protected PDF?
Not directly. Encrypted files are refused with a message asking you to remove the protection first. Unlock it with the PDF unlocker if you know the password, redact, then add a new password with the PDF password protector if you need one.
Is it safe to redact confidential files here?
Your files are never stored on our servers, nothing is retained after your session, and nothing is used for training. The original stays untouched, and only the redacted copy is downloaded.
Redacted and ready to send? Trim the file with the PDF compressor, pull out only the pages you need with the PDF splitter, join several redacted files with the PDF merger, or mark a copy as confidential with the PDF watermark tool. Curious how tools like this are built? Try our free full-stack web development course.