NET offers support both for the old Excel 97-2003 format (.xls) and for the new Excel 2007, Excel 2010, Excel 2013, Excel 2016 and Excel 2019 (.xlsx. NET managed assembly and does not depend on Microsoft Office Excel. NET platform - create new Excel documents from template, edit existing Excel documents and convert Excel files. NET offers object model Excel API for speeding up Excel programming in. NET 6.0, MonoAndroid and Xamarin.iOS) application. NET API that can be used to create, read, write, convert and print Excel files in any type of.