| xlse | Document Manager Encrypted XLS Document |
| xlshtml | Microsoft Excel HTML Spreadsheet |
| xlsl | Document Manager Locked Excel Document |
| xlsm | Microsoft Excel 2007 Document |
| xlsmhtml | Microsoft Excel HTML Spreadsheet |
| xlst | OnlyOffice Internal XLSX Document |
| xlsx | Microsoft Excel 2007 Document |
| xlsxe | Document Manager Encrypted XLSX Document |
| xlsxl | Document Manager Locked XLSX Document |
| xlt | Microsoft Excel Template |
| xlthtml | Microsoft Excel HTML Spreadsheet Template |
| xltm | Microsoft Excel 2007 Template with Macros |
| xltx | Microsoft Excel 2007 Template |
| xlv | Microsoft Excel VBA Module |
| xlw | Microsoft Excel Workbook Document |
| xlw3 | Microsoft Excel 3 for Mac Workbook Document |
| xlw4 | Microsoft Excel 4 for Mac Workbook Document |
| xlw5 | Microsoft Excel 5 for Mac Workbook Document |
| xlxml | Microsoft Excel XML Worksheet |
| xlz | Open Language Tools XLIFF Archive |
| xmap | XMind 2007/2008 Workbook |
| xmcd | Mathcad Worksheet Document |
| xmcdz | Mathcad Compressed Worksheet |
| xmct | Mathcad XML Worksheet Template |
| xmind | XMind Workbook |
| xml | Extensible Markup Language File |
| xmls | Microsoft Excel 2003 XML Document |
| xmn | Sprintometer Document |
| xmp | XMind Markers Package |
| xmt | Romulus 3D Modeler Data |
| XMind Template |
| xod | Silverlight XPS Document |
| xoi | eZediaMX Locked Presentation Document |
| xopp | Xournal++ Notebook |
| xov | Rapidform XOV 3D Model |
| xpd | XML Pipeline Document |
| xpdl | XML Process Definition Language Document |
| xpf | Homestead Sitebuilder Document |
| X-Stitch Studio Design |
| xpr3 | QuarkXPress for Mac Document |
| xps | NetSim Lab Documentation Data |
| XML Paper Document |
| xpwe | PriMus XML Exchange Document |
| xrw | Architag XRay XML Editor Document |
| xs3 | XESS Worksheet |
| xs4 | XESS Worksheet |
| xs5 | XESS Worksheet |
| xsc | Transcribe! Transcription Document |
| xscscpt | Transcribe! Script |
| xsd | Microsoft InfoPath XML Schema |
| Pattern Maker Design |
| xsf | Microsoft InfoPath Form Definition |
| xsh | Xshade 3D Model |
| xsl | Extensible Stylesheet Language Transformations |
| xslt | Extensible Stylesheet Language Transformations |
| xsn | Microsoft InfoPath Form Template |
| xsp | Cross Stitch Pro Design |
| xss | Ability Office Spreadsheet |
| Cross Stitch Pro Read-only Design |
| xsslog | Microsoft SharePoint WorkSpace Groove Log Data |
| xssr | Microsoft SharePoint Workspace Data |
| xswriter | TechWriter for XML Schemas Document |
| xsx | Microsoft XML Schema Designer View |
| xtg | QuarkXPress Tags File |
| xtp | xTime Project Document |
| xtps | xTeam Document |
| xtrn | Call Report Pro XBRL Instance Document |
| xv0 | Extensible Virtual World Description Language Document |
| xv1 | Extensible Virtual World Description Language Document |
| xv2 | Extensible Virtual World Description Language Document |
| xv3 | Extensible Virtual World Description Language Document |
| xvi | XTherion Vector Image |
| xvl | Extensible Virtual World Description Language Document |
| xwf | OmniPage Workflow |
| xwp | Xerox Writer Text Document |
| xxn | Dimenzo Text Editor Document |
| xy | XyWrite Document |
| xy3 | XyWrite III Document |
| xy4 | XyWrite IV Document |
| xy4v | XyWrite IV Document |
