The Xlsx Toolkit is a software add-on for LabVIEW. The add-on provides a LabVIEW API that you can use to create workbooks, worksheets, and charts as Microsoft Excel Open XML Format Spreadsheet (.xlsx) files. The add-on does not require ActiveX, Component Object Model (COM), or Excel to create .xlsx files. You also can open and edit existing .xlsx files. You can use the Xlsx Toolkit to read and write numbers, strings, timestamps, and clusters, and apply style and formatting to cell data.