Password Protect PDF

Password protect a PDFwithout uploading it.

PDFBook lets you password protect a PDF on your own device. When the Creator builds a PDF, it can apply a password and encryption to the output file, so a locked, secure PDF is produced without the file ever leaving your computer. Unlike cloud tools that require you to upload your document first, PDFBook adds the password locally on Windows, macOS, and Linux. To encrypt an existing PDF straight from your browser, PDFBook's online Protect PDF tool does the same thing client-side. And when you open a PDF that is already password-protected, PDFBook remembers the password per book so you do not have to retype it every time.

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Add a password on your device

The Creator applies a password and encryption to the PDF it produces, so you can lock a PDF locally. The file is protected as it is written, with no cloud step in between.

Nothing is uploaded

Your PDF never leaves your computer. Unlike online services that require uploading the document to a server before encrypting it, PDFBook secures the file entirely on your device.

Remembers the password per book

When you read a PDF that is already password-protected, PDFBook stores the password per book, so you unlock it once instead of retyping it on every open.

Private by design, no account

No sign-up, no telemetry, no cloud. Adding a password and reading protected PDFs both run locally, the same privacy-first approach as the rest of the app.

Your files never leave your computer

How PDFBook helps you password protect a PDF

  • Add a password to a PDF as the Creator builds it on your device
  • Encrypt the output PDF so it stays a secure, locked file
  • Keep the document local: nothing is uploaded to a server
  • Encrypt an existing PDF from your browser with the client-side Protect PDF tool
  • Open a password-protected PDF and let PDFBook remember the password per book
  • Skip retyping the password every time you reopen a protected book
  • Works on Windows, macOS, and Linux with no account or telemetry
  • PDFBook does not remove or crack DRM or passwords you do not own

Lock your PDF, privately.

Add a password and encryption to your PDF on your own device, with nothing uploaded. Free for 50 books, $89 once for Lifetime.

Download PDFBook freeSee Lifetime ($89)

Frequently asked questions

How do I password protect a PDF without uploading it?+
Use PDFBook's Creator: when it builds your PDF, it can apply a password and encryption to the output file. The whole process runs on your device, so the document is never uploaded to a server. You end up with a locked, secure PDF created locally.
Can I encrypt an existing PDF from my browser?+
Yes. PDFBook's online Protect PDF tool adds a password to an existing PDF client-side, in your browser, so the file is encrypted without being sent to a server. It does the same on-device protection as the desktop app.
Does PDFBook remember the password for a protected PDF I'm reading?+
Yes. When you open a PDF that is already password-protected, PDFBook stores the password per book. You unlock it once, and on later opens you do not have to retype it.
Can PDFBook remove a password or DRM from a PDF I don't own?+
No. PDFBook can add a password and encryption to PDFs you create, but it does not remove or crack DRM or passwords you do not own.
Is adding a password to a PDF in PDFBook private?+
Yes. PDFBook is local-first: encrypting a PDF with the Creator or the client-side Protect PDF tool happens on your device, with no upload, no account, and no telemetry. Your document never reaches a third-party server.
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