File types
Confidencial supports multiple types of files. Files are protected either in-app (using add-ins or the Confidencial desktop and web app) or through Confidencial’s “.c11” format.
Natively-protected filesMicrosoft Word and ExcelPDF filesImages (JPEG and PNG).C11-protected files and file bundles
Natively-protected files
Confidencial supports several types of files natively. That is, Confidencial encrypts content within these types of files while preserving the native format of the file. These file types include Word docs (.docx), Excel workbooks (.xlsx), and portable document format files (.pdf).
Microsoft Word and Excel
When protected with Confidencial’s Microsoft Office add-ins, files encrypted in Word and Excel maintain their original format, meaning that the files remain valid Word (Excel) files and can be opened in Word (Excel), regardless of whether the Confidencial add-in is installed or not. However, only authenticated users with the Confidencial add-in installed can see content that is encrypted for them.
See 
Encrypting an entire Word document, 
Encrypting parts of a Word document, and 
Decrypting a Word document for more information
PDF files
Confidencial supports native (format-preserving) protection of PDF files through its desktop and web apps using the PDF Protector. Users are able to open existing PDF documents and protect the entire document or parts of the document for a specific set of recipients. Since Confidencial-protected PDF documents are valid PDF files, they can be opened in any PDF viewer. However, only authenticated users with the Confidencial desktop or web app can view (decrypt) protected parts of a Confidencial-protected PDF file.
See 
Sending secure PDFs with Confidencial and 
Viewing secure PDFs with Confidencial for more information
Images (JPEG and PNG)
Just like for PDF files, Confidencial also supports native (format-preserving) protection of JPEG and PNG images in its desktop and web apps. Confidencial users can load an image in Image Protector to protect all or parts of an image. Again, like PDF files, protected images remain in their native format, so they can continue to be viewed in standard (default) images viewers with unprotected parts continuing to be visible. However, one must use the Confidencial desktop or web app (and be authorized) to view protected portions of images.
See Sending secure images with Confidencial and Viewing secure images with Confidencial for more information
.C11-protected files and file bundles
All files types that aren’t natively supported by Confidencial’s apps and add-ins can nonetheless still be protected by encrypting them with Confidencial’s .c11 file format. Like natively-supported file types, users encrypt other file types for a specific set of recipients. Users may protect either a single file or a bundle of files in this manner. Encryption and decryption can be performed in either the desktop or web app.
See Encrypting files and folders and Decrypting a .c11 file or .c11.zip file bundle for more information