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PDF Password Protect

Add password protection to your PDF files — free, browser-based, no upload.

Drag & drop a file here, or browse

PDF file

Max 100MB per file

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Password Protect PDF — Free & Private

Add password protection to your PDF files directly in your browser. Set a user password to restrict who can open the document, and an optional owner password to control editing and printing permissions. All encryption happens client-side — your files are never uploaded to any server.

How to use PDF Password Protect

  • Upload a PDF file.
  • Enter a user password (required to open the PDF).
  • Optionally set an owner password for permission restrictions.
  • Click "Protect PDF" to encrypt and download.

Features

  • User password protection — Require a password to open the PDF document.
  • Owner password (optional) — Restrict editing, copying, and printing permissions.
  • Permission controls — Fine-grained control over printing, copying, and modification.
  • 100% browser-based — Files never leave your device. Complete privacy.
  • No sign-up, no watermarks — Completely free encryption.
  • Instant download — Protected PDF downloads automatically.

Frequently Asked Questions

How do I add a password to a PDF for free?

Upload your PDF to UtilHub's PDF Password Protect tool, enter your desired password, and click "Protect PDF." The encrypted file downloads automatically. All processing happens in your browser — no server upload required.

What is the difference between user and owner passwords?

A user password is required to open and view the PDF. An owner password controls permissions like printing, copying text, and editing. You can set both for maximum security, or just a user password if you only want to restrict access.

Is browser-based PDF encryption secure?

Browser-based encryption using pdf-lib provides standard RC4 40-bit encryption, which is sufficient for basic protection. For highly sensitive documents requiring AES-256 encryption, consider using desktop software like Adobe Acrobat. The advantage of our tool is that your files never leave your device.