Honest comparison

clean.ink vs macOS Preview for redacting PDFs

Preview can truly redact — if you use the right tool in it. Since macOS Big Sur, Preview’s Markup toolbar includes a dedicated Redact tool that permanently removes content. Right next to it sits the shape tool, which draws an identical-looking black box that removes nothing. clean.ink’s difference isn’t privacy — both are local — it’s that clean.ink finds the sensitive fields for you, every box destroys content by design, and it runs on any OS.

Last updated July 9, 2026

Side by side

 clean.inkmacOS Preview
True redaction (content destroyed)Yes — covered content is removed from the exported fileYes — with the Redact tool (macOS 11+); shapes only cover
Document stays on your deviceAlways — all processing is in-browserAlways — Preview is a local app
Finds the sensitive fields for youYes — auto-detects SSNs, accounts, salaries, addresses, and moreNo — you locate every instance yourself
Guards against the cover-only mistakeEvery box destroys content — there is no cover-only toolRedact and shape tools sit side by side and look identical
Works onAny modern browser — macOS, Windows, Linux, mobileMac only
Scanned documentsOn-device OCR recovers text, then detection runsNo OCR — a scan is just an image to Preview
PriceFree preview · $6.59 once for clean downloadsFree, preinstalled on every Mac

Preview capabilities as documented by Apple for macOS 11 and later; behavior can differ on older versions.

The one Preview mistake that leaks documents

Open a PDF in Preview, draw a black rectangle over your SSN with the shape tool, save, send. The document looks redacted. It isn’t: the rectangle is an annotation sitting on top of intact text, and anyone can select through it, copy, and paste your SSN out — or just delete the shape. Preview’s real Redact tool warns you that content will be permanently removed; the shape tool says nothing, because it isn’t removing anything.

If you use Preview, use Tools → Redact and then verify the saved file: select-all, copy, paste into a text editor, and search for what you removed. The full test is in Can redacted PDFs be un-redacted?

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Auto-detection · every box destroys content · any OS

Questions

Can macOS Preview really redact a PDF?
Yes — on macOS Big Sur (11) and later, Preview's Markup toolbar includes a dedicated Redact tool that permanently removes the content when you save. The danger is that Preview's rectangle/shape tool produces an identical-looking black box that only covers the text, leaving it selectable in the file. Real redactions and fake ones look the same on screen.
When is Preview the better choice?
When you're on a Mac, the document has only a couple of spots to remove, and you know exactly where they are. Preview is free, already installed, and fully local. Just make sure you use the Redact tool — not a drawn rectangle — and verify the saved file.
When is clean.ink the better choice?
When you don't want to hunt for the sensitive fields yourself. clean.ink auto-detects SSNs, account and routing numbers, salary amounts, addresses, and dozens of other identifiers, and walks you through each in a review queue — on any operating system, in the browser, with the document never uploaded. It's $6.59 once for clean downloads; previewing is free.
Is Preview private? Does it upload my document?
Preview is a local application — your document stays on your Mac, which is genuinely private. clean.ink matches that (all processing is in-browser, no upload) while adding automatic detection and a verifiable preview, and working on Windows, Linux, and mobile too.