Alphabetically: X
Extension File Description File Type
.x
Lex Source Code File
Developer
.x32
Adobe Xtra File
Plugin
.x3d
Xara3D Project
3D Image
.x3f
SIGMA X3F Camera RAW File
Raster Image
.x4k
XML4King Configuration File
Settings
.x64
Commodore 64 Disk Image
Disk Image
.xa
The Sims Audio File
Audio
.xaml
XAML File
Developer
.xap
Silverlight Application Package
Executable
.xar
Xara Xtreme Drawing
Vector Image
.xas
Pro/ENGINEER Assembly Instance Accelerator File
Data
.xba
OpenOffice.org Basic Module File
Plugin
.xbap
XAML Browser Application File
Executable
.xbc
SMART Notebook File
Data
.xbe
Xbox Executable File
Game
.xbk
SMART Notebook File
Data
.xbl
Extensible Binding Language File
Web
.xbm
X11 Bitmap Graphic
Raster Image
.xbsav
Mass Effect 2 Xbox Saved Game
Game
.xbt
SMART Notebook Template File
Data
.xcf
GIMP Image File
Raster Image
.xcode
Xcode Project
Developer
.xcodeproj
Xcode Project
Developer
.xcu
OpenOffice.org Configuration File
Settings
.xdb
Symantec Virus Database File
Data
.xdl
XML Schema File
Text
.xdp
XML Data Package
Data
.xdr
XML-Data Reduced File
Settings
.xds
DS Game Maker Project File
Game
.xdw
Fuji Xerox DocuWorks File
Layout
.xef
eManager Form Data
Data
.xem
eManager Metered Units
Settings
.xen
Guitar Hero III Data File
Game
.xep
eManager File Packaging Information
Settings
.xes
eManager Skins Definition
Settings
.xet
eManager Process Definition
Settings
.xev
eManager Auto-Update File
Settings
.xex
Xbox 360 Executable File
Game
.xez
eManager Template Package
Compressed
.xfd
XFD File
Data
.xfdf
Adobe Acrobat XFDF File
Data
.xfdl
XFDL File
Web
.xfl
Flash Movie Archive
Video
.xfn
Ventura Printer Font
Font
.xfo
XSL-FO Formatted Form
Data
.xfs
eRacer Sound File
Audio
.xft
Adobe Form Designer 5.0 File
Data
.xgs
XACT Global Settings File
Settings
.xht
XHTML File
Web
.xhtm
Extensible Hypertext Markup Language Document
Web
.xhtml
Extensible Hypertext Markup Language File
Web
.xi
Fasttracker 2 Extended Instrument File
Audio
.xib
Interface Builder File
Developer
.xif
ScanSoft Pagis File
Layout
.xl
Excel Spreadsheet
Spreadsheet
.xla
Excel Add-In File
Plugin
.xlam
Excel Open XML Macro-Enabled Add-In
Plugin
.xlb
Excel Toolbars File
Settings
.xlc
Excel Chart
Data
.xlf
XLIFF Document
Text
.xlgc
ExpressK Database File
Data
.xlk
Excel Backup File
Backup
.xll
Excel Add-In File
Plugin
.xlm
Excel Macro
Executable
.xlnk
XML Shortcut File
Misc
.xlr
Works Spreadsheet
Spreadsheet
.xls
Excel Spreadsheet
Spreadsheet
.xlsb
Excel Binary Spreadsheet
Spreadsheet
.xlshtml
Microsoft Excel HTML Spreadsheet
Spreadsheet
.xlsm
Excel Open XML Macro-Enabled Spreadsheet
Spreadsheet
.xlsmhtml
Microsoft Excel MIME HTML Spreadsheet
Spreadsheet
.xlsx
Microsoft Excel Open XML Spreadsheet
Spreadsheet
.xlt
Excel Template
Data
.xlthtml
Microsoft Excel HTML Spreadsheet Template
Spreadsheet
.xltm
Excel Open XML Macro-Enabled Spreadsheet Template
Spreadsheet
.xltx
Excel Open XML Spreadsheet Template
Spreadsheet
.xlv
Excel Visual Basic Module
Plugin
.xlw
Excel Workspace File
Misc
.xm
Fasttracker 2 Extended Module
Audio
.xmb
Age of Empires Game Data File
Game
.xmcd
Mathcad Worksheet File
Data
.xmcdz
Mathcad Compressed Worksheet File
Compressed
.xmd
GameJack Disc Image
Disk Image
.xmf
Extensible Music File
Audio
.xmi
Extended MIDI File
Audio
.xml
XML File
Data
.xmlper
LeCroy Binary Waveform File
Data
.xmmap
MindManager XML Map File
Vector Image
.xmp
Extensible Metadata Platform File
Misc
.xmpz
Miradi XML Project File
Data
.xmz
FastTracker 2 Extended Module
Audio
.xnk
Exchange Shortcut
Misc
.xnt
QuarkXPress Extension File
Plugin
.xof
Reality Lab 3D Image File
3D Image
.xol
Swiss Map Overlay
GIS
.xom
Worms 3D Object File
Game
.xoml
Windows Workflow File
Developer
.xp
Fastracker 2 Pattern
Audio
.xpaddercontroller
Xpadder Controller Profile
Settings
.xpd
XML Pipeline Document
Web
.xpg
Autoplay Media Studio Exported Page
Data
.xpi
Mozilla Installer Package
Compressed
.xpj
RoboHelp HTML Project File
Data
.xpk
WWE RAW Model File
Game
.xpl
LcdStudio Playlist File
Settings
.xpm
X11 Pixmap Graphic
Raster Image
.xpr
Pro/ENGINEER Part Instance Accelerator File
3D Image
.xps
XML Paper Specification File
Layout
.xpt
Mozilla Firefox Component
Plugin
.xqt
SuperCalc Macro File
Executable
.xrm-ms
Microsoft Security Certificate
System
.xrns
Renoise Song File
Audio
.xrp
RationalPlan Project File
Data
.xry
XRY Data File
Data
.xs
Age of Empires 3 Map AI Generator
Game
.xsb
XACT Sound Bank
Audio
.xsd
XML Schema Definition
Developer
.xsi
Softimage XSI 3D Image
3D Image
.xsiaddon
Softimage Add-on File
Plugin
.xsl
XML Style Sheet
Data
.xslt
XSL Transformation File
Data
.xsn
InfoPath Form Template File
Data
.xspf
XSPF Playlist File
Audio
.xst
WebSphere Query Template
Settings
.xsvf
Xilinx Serial Vector Format File
Data
.xsx
Visual Studio XML Schema Layout File
Developer
.xt
Fastracker 2 Track
Audio
.xtg
Extensible TreeGraph File
Data
.xtl
Vietcong Data File
Game
.xtm
Xtremsplit Data File
Data
.xtp
AutoCAD Exported Tool Palettes File
Settings
.xtreme
Winstep Xtreme Theme Pack
Settings
.xul
XML User Interface Language File
Web
.xv0
Lattice XVL Structure File
3D Image
.xv3
Lattice XVL Geometry File
CAD
.xvid
Xvid-Encoded Video File
Video
.xwb
XACT Wave Bank
Audio
.xwd
X Windows Dump Image
Raster Image
.xwf
OmniPage Workflow File
Misc
.xwk
Crosstalk Communicator Keyboard Mapping File
Settings
.xwp
XMLwriter Project
Text
.xws
Xara Web Designer Graphic
Web
.xx
XXEncoded File
Compressed
.xxd
Brixx Planner Calendar
Data
.xxe
XXEncoded File
Encoded
.xxx
Compucon Singer Embroidery File
Misc
.xy
XYWrite Document
Text
.xy3
XYWrite III Document
Text
.xyp
XYWrite Plus Document
Text
.xys
XYplorer Script File
Executable
.xyw
XYWrite for Windows Document
Text
.xyz
Molecule Specification File
Data
.xz
XZ Compressed Archive
Compressed
.xzfx
ZipLogix ZipForm File
Layout
.x_b
Parasolid Model Part File
CAD
.x_t
Parasolid Model Part File
CAD