Password-protect any PDF online for free — uses AES-256 encryption. Set open and permissions passwords. File never leaves your device. No login needed. PDFworld.
This tool uses highly reliable 128-bit encryption perfectly balanced for broad compatibility across all major PDF viewers (Adobe Acrobat, Chrome, Firefox, Safari, iOS plugins, and Android).
The Owner password controls permissions. The User password controls document opening. You can set both, or just the Owner password to restrict actions without requiring a password to open.
No. All encryption runs entirely in your browser. Your file never leaves your device.
No. The encryption cannot be brute-forced in any reasonable time. Store your passwords in a password manager before locking your PDF.