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Protect a PDF

Add an opening password to your PDF. Pages are rasterized to ensure encryption.

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2Process
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Password Protect PDF Free Online — Encrypt PDF with a Password

FusionPDF's PDF protection tool lets you add a password to any PDF directly in your browser. Set an open password to restrict who can view the document, or set permissions passwords to control printing, copying, and editing rights. All encryption happens locally — your file never reaches a server.

How to Password Protect a PDF

Drop your PDF into the upload area. Enter the password you want to set — either a user password (required to open the file) or an owner password (controls editing and printing permissions). Choose the encryption level (128-bit RC4 or 256-bit AES). Click Protect and download your encrypted PDF immediately.

When to Password Protect a PDF

Password protection is useful when sharing confidential documents via email or cloud storage, when distributing proprietary content that should not be freely copied or printed, when sending sensitive personal data that requires access control, or when complying with policies that require document-level access restrictions.

Why Protect PDFs with FusionPDF

FusionPDF encrypts PDFs locally in your browser using PDF-lib — the password and the document content never leave your device. The tool is free, requires no account, and supports both user and owner passwords with AES-256 encryption. Your protected PDF downloads immediately after encryption.

Want to understand how browser-based PDF tools differ from server-based ones from a privacy standpoint? Read our complete PDF privacy guide — it covers what actually happens when you upload a file to a PDF tool, GDPR compliance, and how to verify any tool's behavior in 60 seconds.