.UPX File Extension

Ultimate Packer for eXecutables automatically unpacks UPX files when they are executed. On some operating systems , it stores the unpacked file in memory using the in-place technique. On other operating systems, it creates a temporary file using the extraction technique.

NOTE: UPX files rarely use a ".upx" file extension. Rather, they most often use their original file extension after being compressed.

To open a .upx file, you need compatible software that supports this file format.