Files with the .key file extension have usually been created by the Apple Keynote presentation software. Keynote was developed by Apple and is run on the Mac operating system. The KEY files created by this software are similar to PowerPoint files, but they are for Mac users and are not functional on Windows computers.
The KEY files that are created by Keynote contain slides that include text, images, presentation transitions and XML data. This data is then shown in a presentation style format when a user launches the file.
The .key file extension is also used by the AntiVir Personal Edition software. The AntiVir Personal Edition software is a free anti-virus application that can be downloaded from the Internet.
Try a universal file viewer
File.org aims to be the go-to resource for file type- and related software information. We spend countless hours researching various file formats and software that can open, convert, create or otherwise work with those files.
If you have additional information about the KEY file format or software that uses files with the KEY suffix, please do get in touch - we would love hearing from you.