You can also choose Tools > Redact, to activate the redaction tool, without engaging Markup. Open a PDF in Preview, then click the Markup button (top right), then click the Redact button (top left). It’s important to always upgrade to the newest macOS version for maximum security.) (Note that this redaction feature was introduced in macOS Big Sur, and also works in macOS Monterey or later. While this isn’t a simple process, it is fast and effective.įortunately, if you use a Mac, you have access to a much more powerful redaction tool in Preview, the app you can use for viewing PDFs and images. Essentially, it attempts to see what characters would like like when pixelated, then, through a sort of reverse engineering, figures out the original text. It looks like this:īut a security researcher at Bishop Fox has shown that this sort of pixelization is reversible, using a simple tool. There are a number of ways you can do this, and one way that has been common for many people is using apps to pixelate the text you want to hide. For example, you may need to provide a bank statement to someone to prove you have a bank account, but not want to show the balance.

Sometimes you want to share a PDF with someone, yet hide some of the information. How To Securely Redact Text in PDFs with Apple Preview on Mac

How to encode backdoor in pdf for mac