By default, all software supports multiple file extensions. Apple Numbers supports at least 4 different file extensions. The basic files that Apple Numbers supports are .XLSX. However, not all of the extensions listed on the list are always used to save the effects of work in Apple Numbers. Very often, files with such extensions are used as source data files used by Apple Numbers.
Apple Numbers can be used to convert file formats between the file extensions listed below. You can open a file with one of the file extensions below via Apple Numbers and try to save it in another file format, also supported by Apple Numbers.