File with .SWI extension contains animation, program or advanced application project created with Flash technology. SWI files were used by Windows SWiSH software, an alternative to Adobe Flash, to create Flash applications. SWiSH software offers easy-to-use interface and plethora of functions at a relatively low price. As of 2011, the software is no longer developed and supported: SwiSHzone.com, developer of the software, closed in 2016.

Finished project can be exported either as standard SWF file, AVI video file format or Flash Projector executable file. SWI file can be used to create website projects eith the option to access database information. SWI files may also be used to convert video files and presentation document files to Flash files.