Encrypt PDF

Lock your PDF behind a password so only authorized people can open it. BentoPDF uses 256-bit AES encryption -- the same standard used by banks and government agencies -- applied entirely in your browser via QPDF.

How It Works

1. Upload a PDF file.
2. Enter a User Password (required). This is the password people will need to open the file.
3. Optionally enter an Owner Password. When set, the PDF gains usage restrictions that prevent printing, editing, copying, and annotating.
4. Click Encrypt PDF.
5. Download the encrypted file.

Password Types

User Password (Required)

The user password is what recipients type to open the PDF. Without it, the document is completely inaccessible. Every encrypted PDF must have one.

Owner Password (Optional)

The owner password controls what an authorized user can do after opening the file. When you set a distinct owner password, BentoPDF automatically applies the strictest restriction set:

• Modification disabled
• Extraction/copying disabled
• Printing disabled
• Annotation disabled
• Form filling disabled
• Document assembly disabled

If you leave the owner password blank, the PDF is encrypted (it still requires the user password to open) but has no usage restrictions once opened.

Encryption Details

• Algorithm: AES-256 (256-bit Advanced Encryption Standard)
• Key length: 256 bits
• Standard: PDF 2.0 encryption (QPDF implementation)

AES-256 is computationally infeasible to brute-force with current technology. The security of your encrypted PDF depends entirely on the strength of your password.

Use Cases

• Protecting confidential financial reports before emailing them
• Securing legal documents shared with opposing counsel
• Adding a password to medical records or personally identifiable information
• Distributing paid content (e-books, reports) with access control
• Complying with data protection policies that require encryption at rest

Tips

• Use a strong, unique password. A 12+ character passphrase with mixed case, numbers, and symbols is ideal.
• Share the password through a separate channel (phone, text message) -- never in the same email as the PDF.
• If you only need to restrict actions (no printing, no copying) without requiring a password to open, use the Change Permissions tool instead.

Related Tools

• Decrypt PDF -- remove encryption when you know the password
• Change Permissions -- modify specific usage restrictions
• Remove Restrictions -- strip all security from a PDF
• Sanitize PDF -- remove hidden content before encrypting