Free Protect PDF with Password Encryption (AES-128 / AES-256)

Encrypt and password-protect sensitive PDF documents with standard AES encryption. Prevent unauthorized opening, copying, or printing.

🔒 100% In-Browser & Zero Server Uploads

About Protect PDF with Password Encryption

Applies standard AES password encryption to PDF document security dictionaries, requiring a password before opening in Acrobat, Chrome, or Apple Preview.

How to Use Protect PDF with Password Encryption Online

  1. Upload your PDF file.
  2. Type your secure password.
  3. Click Encrypt PDF and download your locked document.

Frequently Asked Questions

Can someone open the protected PDF without the password?
No, standard AES encryption locks the file data so it cannot be read without the correct decryption key.