This page provides a list of those file extensions that start with .x. The information given below is a summary and further details can be found by clocking on the summary next to the file extension of interest.

.x3d mesh file | RPC language source file.
.xapSilverlight application.
.xarVector graphics file | Excel auto-recover save file.
.xbmX windows cursor or bitmap.
.xcfGIMP image file.
.xhtmlXHTML web page
.xifImage file | Pagis scanned document image file.
.xlaMicrosoft Excel VBA add-in file.
.xlamMicrosoft Excel add-in file.
.xlbMicrosoft Excel toolbar file.
.xlcMicrosoft Excel Chart file.
.xldMicrosoft Excel Dialog file.
.xlkMicrosoft Excel Archive file.
.xllMicrosoft Excel add-in file.
.xlmMicrosoft Excel Macro file.
.xlrMicrosoft Works spreadsheet.
.xlsExcel spreadsheet.
.xlsbExcel binary workbook.
.xlsmMacro enabled Microsoft Excel (XML) Spreadsheet file.
.xlsxExcel (XML) Spreadsheet file.
.xltExcel template.
.xltmExcel macro enabled template file.
.xlvMicrosoft Excel Module file.
.xlwMicrosoft Excel Workspace file.
.xmlGeneric XML file extension.
.xpfHomestead SiteBuilder file.
.xpiCross-Platform Installer Module.
.xpsXML Paper Specification document.
.xrpRationalPlan project file | Gamemaker external resources file.
.xsdXML schema definition file.
.xsltExtensible Style-sheet Language Transformation file.
.xspfXML Shareable Playlist Format file.
.xtfeXtended Triton Format file.
.xxxVirtual PC Temporary file.

For further information about the file extension please do click on the summary next to the file extension in the list above.

We would like this listing to be complete and comprehensive, but recognised that we may have missed one and that new file types are being used all the time. So if you know of a file type that we have missed that should be listed here then please let us know.