How to Redact a PDF on Mac Without Adobe Acrobat

Why Removing Sensitive Information from PDFs Matters

PDFs are everywhere in professional life — contracts, invoices, medical records, legal filings, HR documents. The problem is that when you share a PDF, you often share more than you intend to. A contract might contain a client's home address. An invoice might expose a bank account number. A medical record might include a patient's full name and date of birth alongside a diagnosis.

Removing sensitive information from a PDF before sharing it is not just good practice — in many cases it's a legal requirement. GDPR requires that you only share personal data that is necessary for the purpose. HIPAA prohibits sharing Protected Health Information (PHI) without authorization. FRCP rules govern what identifying information must be redacted in court filings.

This guide covers exactly how to do it on a Mac, permanently and correctly.

What Counts as Sensitive Information in a PDF?

Sensitive information — also called personally identifiable information (PII) — includes anything that can identify a specific individual or expose confidential data:

• Names and surnames
• Email addresses
• Phone numbers
• Physical addresses
• Bank account numbers and financial data
• Social Security numbers and national ID numbers
• IP addresses
• Medical record numbers and health information
• Dates of birth
• URLs and usernames

In a PDF, this data can appear anywhere — in the visible text, in form fields, in metadata, or even in document properties. A complete redaction process should address all of these locations.

Method 1: Use BlurData (Automatic Detection)

BlurData is a macOS app purpose-built for removing sensitive information from PDFs and screenshots automatically. Rather than manually hunting for every name, email, and account number, BlurData scans the document and flags all detected PII for review.

Here is how it works:

1. Drag your PDF into BlurData
2. BlurData scans the document and highlights detected sensitive data — emails, names, phone numbers, IP addresses, monetary values, and more
3. Review and confirm which items to redact
4. Export the redacted PDF

The entire process runs offline on your Mac. No data is sent to any server. This is important for GDPR, HIPAA, and any workflow where the document content must not leave your device.

BlurData also supports batch redaction — if you have a folder of PDFs that all need sensitive data removed, you can process them all in one pass rather than one file at a time.

Method 2: Use macOS Preview (Manual, Free)

Apple's built-in Preview app has a basic redaction tool available on macOS Big Sur and later. It is free and requires no installation, but it is entirely manual — you must select each piece of sensitive text yourself.

1. Open your PDF in Preview
2. Go to Tools → Redact
3. Click and drag to select the text or area you want to remove
4. Click Apply Redactions
5. Save the file

The limitation: Preview does not auto-detect sensitive data. If your PDF has 50 pages and dozens of email addresses, you must find and select each one individually. For a short document with a single piece of sensitive data, Preview is fine. For anything more complex, it becomes error-prone.

One important note: in older versions of macOS, the "redaction" in Preview was actually just drawing a black rectangle on top of the text — the underlying text was still present in the file and could be extracted. Make sure you are using a version that permanently removes the content.

Method 3: Use PDF Expert

PDF Expert is a paid Mac app ($79.99/year) with a dedicated redaction tool. It supports both text selection redaction and area redaction, and it permanently removes the underlying content from the file.

1. Open your PDF in PDF Expert
2. Click the Redact tool in the toolbar
3. Select the text or regions to redact
4. Apply and save

PDF Expert is a good option if you already use it for PDF editing and need occasional redaction. It does not offer automatic PII detection — you still need to find sensitive data manually.

What NOT to Do: The "Black Rectangle" Mistake

The most common redaction mistake — responsible for several high-profile data leaks — is drawing a black shape over sensitive text without actually removing it from the file. This is not redaction. The underlying text remains in the PDF and can be revealed by anyone who copies the text, adjusts the layer order, or uses a text extraction tool.

The Epstein documents redaction failure and numerous other cases happened exactly this way. Always verify that the text is actually gone after redaction by attempting to copy text from the redacted area.

What About PDF Metadata?

Even after redacting visible text, a PDF can still contain sensitive information in its metadata — the document title, author name, creation date, or revision history. Before sharing a redacted PDF, consider stripping the metadata as well.

On macOS, you can use the File → Export as PDF option in Preview to create a new file, which often strips some metadata. For thorough metadata removal, dedicated tools or command-line utilities like exiftool provide more control.

Summary: Choosing the Right Method

If you are removing sensitive information from a PDF on Mac and need speed, accuracy, and the assurance that nothing was missed, BlurData is the right tool. Try it free for 7 days.