PDF UtilitiesPDF SecurityFree Tool

Encrypt PDF

Apply AES-256 encryption to a PDF for strong file-level security. Specify open and owner passwords to control both access and usage permissions in a single operation.

How to Use Encrypt PDF
  1. 1Upload the PDF you want to encrypt
  2. 2Enter the open (user) password — required to view the document
  3. 3Enter the owner password — required to change permissions (can be different)
  4. 4Click 'Encrypt PDF' to apply AES-256 encryption
  5. 5Download the encrypted PDF and store both passwords securely
Examples
  • Apply AES-256 encryption to a confidential business acquisition document
  • Encrypt a personal medical record PDF before storing it on a shared network drive
  • Encrypt a signed NDA before sending via unsecured email
  • Add AES encryption to a financial report before sharing with external auditors
Frequently Asked Questions

Both apply a password. Encrypt specifically refers to AES-256 encryption, the strongest available. The Protect tool may use AES-128 by default; Encrypt always uses AES-256 for maximum security.

Advanced Encryption Standard (AES) with 256-bit keys is a military-grade encryption standard. It is computationally infeasible to break without the password, even with modern hardware.

Yes. The open (user) password controls viewing. The owner password controls editing, printing, and copying permissions. They can be different.

AES-256 encrypted PDFs require PDF reader version 1.6 or higher. All modern PDF readers (Acrobat, Chrome, Edge) support this. Very old readers may not.

Yes. AES-256 is used by governments and financial institutions. For PDFs containing highly sensitive personal or financial data, AES-256 is the appropriate choice.

Yes. Encryption runs in your browser. Your PDF and passwords are never transmitted to any server.

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