How to Remove Sensitive Information & Metadata from a PDF on Mac

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 and Document Properties?

Even after redacting visible text, a PDF can still contain sensitive information in its document properties — the title, author name, subject, keywords, creation/modification dates, the application that created the file, and any revision history. Before sharing a redacted PDF, you should strip all of this metadata. See the short version: remove metadata from a PDF on Mac.

How to View PDF Document Properties in PDF Expert on Mac

If you use PDF Expert and want to inspect what metadata your PDF actually contains:

1. Open the PDF in PDF Expert
2. Click File → Show Properties (or press ⌘+D)
3. The Document Properties panel opens, showing Title, Author, Subject, Keywords, Application, PDF Producer, Creation Date, Modification Date, and more
4. Click on any editable field to change it, or clear it entirely
5. Save the PDF — the cleaned metadata is now permanent

PDF Expert lets you edit these fields but doesn't auto-detect what is actually sensitive — you have to know what to remove. Common fields that leak privacy: Author (usually your full name from the system), Title (often the original filename), and PDF Producer (reveals which software you used). Clear those before sharing.

How to Remove PDF Metadata in macOS Preview

Preview can also strip some metadata when you re-export the file:

1. Open the PDF in Preview
2. Choose File → Export as PDF
3. In the dialog that appears, click the small dropdown near the bottom — you can pick a Quartz Filter such as Reduce File Size which discards most metadata
4. Save as a new file

This is faster than PDF Expert for quick metadata cleanup, but it doesn't let you see what metadata existed before stripping it.

How to Remove PDF Metadata from the Terminal (exiftool)

For thorough metadata removal — including XMP packets and hidden custom properties that GUI tools can miss — exiftool is the gold standard:

brew install exiftool
exiftool -all= input.pdf

That single command wipes every metadata tag from the file. Use this for compliance-grade cleanup (legal discovery, FOIA responses, GDPR-sensitive workflows).

What PDF Expert Doesn't Do — and Where BlurData Fits

Editing document properties in PDF Expert handles metadata, but it doesn't help with sensitive data in the body of the PDF — names, email addresses, IBANs, SSNs, account numbers, or anything else embedded in the actual document content. For that, PDF Expert requires you to manually find and select every piece of sensitive text before applying its Redact tool.

BlurData is the complementary tool here: it auto-detects 8 PII types (emails, names, addresses, IPs, URLs, monetary values, account numbers, license plates) in the document body and lets you batch-redact entire folders. It runs fully offline like PDF Expert, but you don't have to scan each page manually. Many users use PDF Expert for metadata + BlurData for body redaction — they cover the two halves of "a fully clean PDF" together.

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. Get BlurData.