XML (eXtensible Markup Language) is widely used format for holding data with user-defined tags, so that users can easily retrieve their data to use it with other applications according to the requirements. Since Excel 2010 has the ability to convert spreadsheet between various formats including HTML, CSV, TXT, DIF, XPS, ODA etc., you can also use it use Excel to convert said formats into XML without having to use any dedicated, third-party application to do the conversion.
Excel 2010, just like previous versions, doesn’t offer a separate tool to perform the conversions, so you have to use the Save As dialog to convert XLSX or other Excel-supported formats to XML format. It must be noted the Excel 2010 saves the spreadsheet in XML Spreadsheet 2003 format, and some new features of your spreadsheet may not work with XML 2003 format. When you attempt to convert Excel 2010 workbook to XML, you can view the Excel Help section to check out the feature that won’t work with XML format. Like other formats, you can access General and Web options while saving the spreadsheet to XML format; before you click Save, click Tool menu to access General options to apply password-protection and Web Options to optimize the spreadsheet for the web.
In order to save/import the worksheet in XML format, click on the File menu and click Save As. This will open Save As dialog. Alternatively, you can also press F12 to bring up Save As dialog. From Save As type options, select XML Data (*.xml). Now click Save to export a worksheet into XML format.