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RedactSnap

How to redact a PDF on a Mac

By RedactSnap ·

Preview, the PDF app built into macOS, has had a Redact tool since macOS Big Sur. It removes the text you select when you save. For scanned pages, PDFs with hidden layers, or when you want the result checked, RedactSnap redacts in your browser and flattens every page on export.

Redact a PDF in Preview

  1. Step 1: Duplicate the PDF first (File > Duplicate). Preview's redactions are permanent once you save and close.

  2. Step 2: Choose Tools > Redact, or click the Redact button in the Markup toolbar. Preview shows a warning that redacted content is removed.

  3. Step 3: Drag over the text or area to hide. Preview draws a black box over it.

  4. Step 4: Save and close. Until you close the file, Edit > Undo removes a redaction.

  5. Step 5: Reopen the saved PDF and use Edit > Find to search for a word you hid. If it is found, it is still in the file.

Where Preview falls short

Preview's Redact tool works on the text you select. PDFs can hold more than that: text in hidden layers, form fields and annotations, text that runs past the edge of the page, and the document's metadata. Eclectic Light warns that a PDF can hold hidden objects that a visible redaction doesn't reach.

Preview also doesn't find anything for you. On a 30-page statement, every account number and email has to be found and boxed by hand. And it is easy to pick the Rectangle shape by mistake, which only draws a box on top.

Redact a PDF on a Mac in your browser

RedactSnap runs in Safari, Chrome or Firefox and doesn't upload the file. It finds common personal data for you, flattens every page to an image on export, and checks the exported file before you download it.

  1. Step 1: Open redactsnap.com/app and drop the PDF on the page. Click Find sensitive data, then Scan document. Smart Scan lists emails, phone numbers, card numbers and US Social Security numbers, and reads scanned pages with OCR.

    Smart Scan findings beside a sample statement in RedactSnap

  2. Step 2: Click Redact all, or Redact on each item, and drag boxes over anything else. Then click Export.

    The Export redacted PDF dialog, with Remove document metadata ticked

  3. Step 3: The tool checks the exported file for selectable text, the words you redacted and metadata. Download it when it says Ready to share.

    The Check and download screen with a preview of the flattened statement

Try it on your own file

The tool opens PDFs, PNGs and JPGs in your browser. The file is not uploaded.

Redact a PDF or image

Sources

Frequently asked questions

Does Preview redact PDFs permanently?

Preview's Redact tool removes the selected text when you save and close the file. A rectangle drawn with the Shapes tool does not; it only covers the text.

Which macOS versions have the Redact tool?

macOS Big Sur (11) and later.

Can Preview redact a scanned PDF?

It can draw a redaction box over a scanned page, but it can't search a scan for text. RedactSnap reads scanned pages with OCR on your device, so Smart Scan can find emails, phone numbers and SSNs on them.

Will the redacted PDF still be searchable?

With Preview, the rest of the text stays searchable. With RedactSnap, pages become images, so nothing in the exported file can be selected or searched.