How to Redact Sensitive Information (SSN, Account Numbers) From a PDF
Black-highlighting text in a PDF doesn't actually remove it — anyone can copy-paste underneath the highlight and read what's "hidden." True redaction deletes the underlying data so it cannot be recovered. Here's how to do real redaction free, in your browser.
The problem
You're sharing a tax document, lease, or court filing publicly or with someone who shouldn't see your SSN, bank account, home address, or signature. The "highlight in black" trick has caused real-world data leaks (the Manafort case, NSA contractor leaks). You need actual deletion.
Use the tool now
Open the edit pdf tool and follow the steps below.
Step-by-step
- 1
Open the Edit PDF tool
Drop your PDF into the editor below. The file is loaded into the browser — nothing uploads.
- 2
Use the Redact tool (not the Highlight tool)
The redact tool draws a black box AND deletes the text underneath. The highlight tool only changes appearance. This distinction is critical.
- 3
Drag rectangles over every sensitive field
SSN, account numbers, signatures, addresses, dates of birth, employer EIN. Don't miss the headers — many forms repeat the SSN at the top of every page.
- 4
Apply redactions
Click Apply Redactions (or equivalent). The tool replaces the text with black rectangles AND scrubs the underlying text content.
- 5
Verify by selecting text
After download, try to select text in the redacted areas. Nothing should select. Open in a different PDF viewer (Chrome, Edge) to double-check.
Pro tips
- •Always work on a copy. Once redactions are applied and saved, the original text is gone.
- •Search for the value (SSN, account number) using Ctrl+F to make sure you didn't miss any occurrences. Multi-page filings often repeat sensitive data.
- •Metadata can also leak data. Run View Metadata after redacting and use Edit Metadata to scrub the author, title, subject, and modification history.
- •For maximum safety, after redacting, run the file through Sanitize PDF to remove embedded objects, hidden layers, and form data that visual redaction won't touch.
Frequently asked questions
Why isn't a black highlight enough?
A highlight is just a colored rectangle drawn over the text. The text remains in the PDF's content stream. Anyone can copy text under the highlight, run text-extraction on the file, or open in a different viewer to read it.
Has black-box redaction actually leaked sensitive data?
Yes — repeatedly. High-profile cases include the 2018 Manafort court filing, multiple TSA documents, and several NSA contractor leaks where reporters copy-pasted under highlights to recover redacted text.
Can redacted text be recovered with software?
If you used true redaction (which deletes the underlying text), no — the data is gone. If you only highlighted, yes — any PDF parser can extract the original.
Should I also flatten the PDF after redacting?
Yes. Flattening converts annotations and form fields into static page content, ensuring no metadata about redaction locations remains.