PDF ToolsProtect PDF
Protect PDF
Add password protection and encryption to your PDF
Drag and drop your files here
or click to browse. Supports PDFs, PNG, JPG, DOCX, and more.
Private.
Encryption
- 🔒 AES-256 — strongest PDF encryption
- 👤 User password — required to open
- 👑 Owner password — controls permissions
About Protect PDF
Modufile's Protect PDF tool adds AES-256 encryption and password protection to your PDF files directly in your browser. You can set a user password (required to open and view the document) and an owner password (required to change permissions such as printing, copying, and editing). All encryption is performed client-side using the MuPDF engine compiled to WebAssembly — your files and passwords are never sent to any server. AES-256 is the strongest encryption standard supported by the PDF specification and is the same level used by financial and government institutions.
Tech Stack
mupdfApplies AES-256 encryption with user and owner password support