Developer File Types
The Developer Files category contains files related to software development. These include programming project files, source code files, code libraries, header files, and class files. Compiled objects and components are also included in this category.
Common developer file extensions include .C, .CS, .M, and .JAVA.
| Extension | File Description | Popularity |
|---|---|---|
| .$01 | DOS Pipe File | Rare |
| .001 | Multimedia Fusion Backup File | Uncommon |
| .4db | 4th Dimension Database Structure File | Average |
| .a | Static Library | Average |
| .a2w | Alice World | Average |
| .ab | Applix Builder File | Rare |
| .abc | ABC Source File | Uncommon |
| .abc | ActionScript Byte Code File | Average |
| .acd | RSLogix 5000 Program | Average |
| .acp | EditPlus Auto-Completion File | Uncommon |
| .act | DS Game Maker Action File | Uncommon |
| .actx | DS Game Maker Action Description File | Uncommon |
| .ada | Ada Source Code | Uncommon |
| .adb | Ada Body File | Uncommon |
| .addin | Visual Studio Add-in Definition File | Average |
| .ads | Ada Specification File | Average |
| .aep | Activ E-Book Project | Average |
| .agi | Asterisk Gateway Interface File | Average |
| .alb | Alpha Five Library | Average |
| .am | Automake Makefile Template | Uncommon |
| .am4 | AutoPlay Media Studio 4 Project File | Average |
| .am5 | AutoPlay Media Studio 5 Project File | Average |
| .am6 | AutoPlay Media Studio 6 Project | Average |
| .am7 | AutoPlay Media Studio 7 Project | Average |
| .anjuta | Anjuta IDE Project File | Uncommon |
| .apa | RSView Development Project Archive | Average |
| .apr | Apadana Project File | Uncommon |
| .aps | Visual C++ Resource File | Average |
| .arsc | Android Package Resource File | Average |
| .art | Artifacts Artifact File | Uncommon |
| .artproj | Artifacts Project | Average |
| .as | ActionScript File | Common |
| .as2proj | FlashDevelop ActionScript 2 Project File | Average |
| .as3proj | FlashDevelop ActionScript 3 Project File | Common |
| .asc | ActionScript Communication File | Common |
| .asi | Alpha Five Variable File | Average |
| .asm | Assembly Language Source Code File | Average |
| .asm | Visual Studio Assembler Source Code File | Average |
| .au3 | AutoIt v3 Script | Average |
| .aut | AutoIt Script File | Uncommon |
| .autoplay | AutoPlay Media Studio Project File | Average |
| .awk | AWK Script | Average |
| .axe | Annotated XML Example File | Uncommon |
| .b | BASIC Source File | Average |
| .bas | BASIC Source Code File | Average |
| .bb | Blitz Source Code File | Average |
| .bbc | BBC BASIC Data File | Average |
| .bbproject | BBEdit Project File | Average |
| .bbprojectd | BBEdit Project Document | Common |
| .bcp | Borland C++ Makefile | Average |
| .bet | BETA Source File | Average |
| .bpg | Borland Project Group | Average |
| .bpl | Borland Package Library | Average |
| .brx | BREW Application Resource File | Average |
| .bs2 | BASIC Stamp 2 Code File | Average |
| .bsc | Visual Studio Source Browser Information File | Average |
| .bsh | BeanShell Script | Uncommon |
| .btn | AutoPlay Media Studio Button File | Uncommon |
| .c | Lite-C Script | Average |
| .c | C/C++ Source Code File | Very Common |
| .cap | Construct Game Development File | Average |
| .car | Brew Component Application Resource File | Average |
| .cbl | COBOL Program File | Average |
| .cbp | Code::Blocks Project File | Average |
| .cc | C++ Source Code File | Average |
| .ccgame | XNA Creators Club Game Package | Average |
| .ccn | Compressed Multimedia Fusion File | Average |
| .ccscc | ClearCase Source Control Info File | Uncommon |
| .cd | Visual Studio Class Diagram | Average |
| .cfc | ColdFusion Component File | Average |
| .cham | Compiled HAM File | Rare |
| .chef | Chef Source Code File | Rare |
| .ci | PolySpace Preprocessed Code File | Rare |
| .class | Java Class File | Very Common |
| .cls | Program Class File | Average |
| .clw | Visual C++ ClassWizard File | Average |
| .cob | COBOL Source Code File | Average |
| .cod | Compiled Source Code | Average |
| .config | Configuration File | Average |
| .cp | Xcode C++ Source File | Common |
| .cp | Captivate Source File | Average |
| .cpb | Comicino Studio Project File | Uncommon |
| .cpp | C++ Source Code File | Very Common |
| .cs | Visual C# Source Code File | Very Common |
| .csi | ContentServ Include File | Average |
| .csi | EdLog Program Data File | Average |
| .csn | Adobe Code Snippet Document | Average |
| .csproj | Visual Studio C# Project | Common |
| .cst | ContentServ Template | Uncommon |
| .ctl | Visual Basic UserControl Object File | Average |
| .ctp | CakePHP Template | Average |
| .ctx | Visual Basic Control Binary File | Average |
| .cu | CUDA Source Code File | Average |
| .cxx | C++ Source Code File | Average |
| .d | D Source Code File | Average |
| .dabriefcase | RemObjects Data Abstract File Briefcase | Uncommon |
| .daconfig | RemObjects Data Abstract Configuration File | Uncommon |
| .dba | DarkBASIC Source Code File | Average |
| .dbml | Visual Studio OR Design File | Average |
| .dbo | DarkBASIC Object | Average |
| .dbpro | DarkBASIC Professional Project File | Average |
| .dbproj | Visual Studio Database Project File | Average |
| .dcp | Delphi Compiled Package | Average |
| .dcproj | Dashcode Project | Common |
| .dcu | Delphi Compiled Unit | Average |
| .dec | Declaration File | Average |
| .def | Module-Definition File | Average |
| .dep | Windows Dependency File | Uncommon |
| .depend | Code::Blocks Dependencies File | Rare |
| .dev | Dev-C++ Project File | Uncommon |
| .dex | Dalvik Executable File | Common |
| .df1 | Omnis Native Datafile | Average |
| .dfk | Dark Flow Project File | Uncommon |
| .dfm | Delphi Form | Average |
| .dis | DisSharp Project File | Rare |
| .dob | Visual Basic UserDocument | Average |
| .dox | Visual Basic Binary UserDocument | Average |
| .dox | Doxygen Documentation File | Uncommon |
| .dpk | Delphi Package | Average |
| .dpl | Delphi Package Library | Average |
| .dpr | Delphi Project | Average |
| .drf | Delphi Resource File | Rare |
| .dsgm | DS Game Maker Project | Average |
| .dsk | Borland Project Desktop File | Average |
| .dsp | Visual C++ 6 Project | Average |
| .dsym | Xcode Debug Symbols File | Uncommon |
| .dtd | Document Type Definition File | Very Common |
| .dylib | Mach-O Dynamic Library | Uncommon |
| .ecp | EasyC Project File | Uncommon |
| .edm | Adobe Extension Data Markup Language File | Uncommon |
| .edml | Adobe Extension Data Markup Language Document | Average |
| .edmx | ADO.NET Entity Data Model Designer File | Average |
| .el | Emacs Lisp Code File | Uncommon |
| .elc | Emacs Compiled Lisp File | Uncommon |
| .ent | External Entity | Average |
| .eql | Embedded SQL File | Average |
| .erl | Erlang Source Code File | Average |
| .ex | Euphoria Source Code | Average |
| .exl | JSDAI Inclusion or Exclusion List | Rare |
| .exp | Symbols Export File | Common |
| .exw | Euphoria Source code File | Average |
| .f | Fortran Source Code | Average |
| .f90 | Fortran 90 Source Code File | Average |
| .fbp | wxFormBuilder Project | Average |
| .fce | ForeUI Custom Element File | Uncommon |
| .fcl | ForeUI Custom Library File | Uncommon |
| .fd | DataFlex Data File | Uncommon |
| .fgl | Fifth Generation Language Source File | Average |
| .filters | Visual C++ Project Filters File | Uncommon |
| .fla | Adobe Flash Animation | Very Common |
| .for | Fortran 77 Source File | Average |
| .fpa | Front Panel Encrypted Order File | Average |
| .fpd | Front Panel Order File | Average |
| .fpm | FPS Creator Map File | Average |
| .fpp | Front Panel Project | Average |
| .fpp | Fortran Source Code | Uncommon |
| .framework | Mac OS X Application Framework | Average |
| .frj | FreeForm-J Project File | Uncommon |
| .frm | Visual Basic Text Form | Uncommon |
| .frx | FoxPro Report | Uncommon |
| .frx | Visual Basic Binary Form File | Average |
| .fs | Visual F# Source File | Common |
| .fsi | Visual F# Signature File | Average |
| .fsproj | Visual F# Project File | Common |
| .fsproj | FireStarter Project File | Average |
| .fsscript | Visual F# Script | Average |
| .fsx | Visual F# Script File | Common |
| .ftl | FreeMarker Template File | Common |
| .ftn | Fortran Source Code File | Average |
| .fxl | FaceFX Language File | Average |
| .fxpl | Adobe Flash FXP Library | Average |
| .gar | GridGain Archive | Uncommon |
| .gbap | GLBasic Project File | Uncommon |
| .gbas | GLBasic Source File | Uncommon |
| .ged | Game Editor Project File | Average |
| .gem | RubyGems Package | Common |
| .glade | Glade Project File | Uncommon |
| .gld | MPLAB C Compiler Linker Script File | Average |
| .global | Global Makefile | Rare |
| .gls | GLScript Game Script | Uncommon |
| .gm | GameMonkey Script | Rare |
| .gm6 | Game Maker 6 Project File | Average |
| .gm81 | Game Maker 8.1 Project File | Average |
| .gmd | Game Maker Program Code | Average |
| .gmk | Game Maker Project File | Common |
| .gml | Game Maker Language File | Uncommon |
| .gmo | GNU Machine Object File | Average |
| .gorm | Gorm Interface Resource File | Average |
| .gpj | jGRASP Project File | Rare |
| .gpj | MULTI IDE Project File | Uncommon |
| .gs3 | GameStarter File | Average |
| .h | C/C++ Header File | Common |
| .hal | HansaWorld Application Language File | Average |
| .has | Haskell Script | Average |
| .hh | C++ Header File | Average |
| .hhh | Power C Precompiled Header File | Uncommon |
| .hpf | High Performance Fortran File | Average |
| .hpp | C++ Header File | Common |
| .hrl | Erlang Header File | Uncommon |
| .hs | Haskell Script | Average |
| .hxx | C++ Source Code Header File | Average |
| .hydra | Hydra Image Filter Program File | Uncommon |
| .i | Visual Studio Intermediate File | Average |
| .i | INTERCAL Source File | Uncommon |
| .idb | Visual Studio Intermediate Debug File | Average |
| .idl | Interface Definition Language File | Average |
| .idt | Windows Installer Database Text Archive File | Average |
| .ilk | Incremental Linking File | Average |
| .iml | IntelliJ IDEA Module | Average |
| .inc | Include File | Average |
| .inl | C++ Inline File | Average |
| .ino | Arduino Sketch File | Average |
| .ipch | Intellisense Precompiled Header File | Average |
| .ipp | Inline Guard Macro File | Uncommon |
| .ipr | IntelliJ IDEA Project File | Average |
| .ipr | InstallShield Professional Project File | Average |
| .isc | Xilinx Device Configuration File | Average |
| .ise | InstallShield Express Project File | Common |
| .ism | InstallShield Project File | Average |
| .ist | InstallShield Project Template File | Average |
| .iws | IntelliJ IDEA Web Page | Average |
| .iwz | InstallShield Express 2 Project File | Uncommon |
| .j | Java Source File | Uncommon |
| .jav | Java Source File | Uncommon |
| .java | Java Source Code File | Very Common |
| .jed | Xilinx JEDEC Programming File | Average |
| .jic | JTAG Indirect Configuration File | Average |
| .jpd | Java Process Definition | Uncommon |
| .jpr | JBuilder Project | Average |
| .jpx | JBuilder Project | Average |
| .jsfl | Flash JavaScript File | Average |
| .jspf | Java Server Page Fragment | Common |
| .jsxinc | ExtendScript Included Script File | Uncommon |
| .kb | C++ Keyboard Script | Rare |
| .kdevdlg | KDevelop Dialog Box File | Rare |
| .kdevelop | KDevelop Project Data File | Average |
| .kdevprj | KDevelop Project File | Average |
| .kdmp | Windows Crash Dump File | Rare |
| .kpl | Kids Programming Language File | Average |
| .l | Lex Source File | Average |
| .lbi | Dreamweaver Library Item | Average |
| .lbs | Omnis Library | Average |
| .lds | Binutils LD Linker Script | Average |
| .lgo | Logo Instructions File | Average |
| .lhs | Literate Haskell Script | Average |
| .licenses | Visual Studio Licensed Classes File | Average |
| .licx | Visual Studio License File | Average |
| .lis | VAX Program Listing | Uncommon |
| .lisp | Lisp Source Code File | Average |
| .list | JAR Index File | Uncommon |
| .lit | Literate Haskell Script | Average |
| .lnt | PC-lint/FlexeLint Configuration File | Average |
| .lol | LOLCODE Source Code FIle | Uncommon |
| .lproj | Localized Project Folder | Average |
| .lrdb | Photoshop Lightroom Database | Uncommon |
| .lrf | Microsoft Linker Response File | Rare |
| .lsp | Lisp Program Source Code File | Uncommon |
| .lua | Lua Source File | Common |
| .lxsproj | Liquid XML Studio Project File | Average |
| .m | Objective-C Implementation File | Very Common |
| .m | Mercury Source Code File | Uncommon |
| .m | MATLAB Source Code File | Common |
| .m4 | Macro Processor Library | Average |
| .magik | Magik Source Code File | Average |
| .mak | Makefile | Average |
| .mako | Mako Template | Uncommon |
| .markdn | Markdown File | Rare |
| .markdown | Markdown Documentation File | Common |
| .mcp | CodeWarrior Project | Average |
| .md | Machine Description File | Uncommon |
| .md | Markdown Documentation File | Common |
| .mdown | Markdown File | Uncommon |
| .med | RSView Development Project | Uncommon |
| .mer | RSView Development Runtime File | Average |
| .mf | Java Manifest File | Average |
| .mfa | Multimedia Fusion Development File | Average |
| .mk | Makefile | Average |
| .ml | ML Source Code File | Average |
| .mlb | Visual FoxPro Library | Uncommon |
| .mm | Objective-C++ Source File | Common |
| .mo | Machine Object File | Average |
| .mod | Fortran Module File | Average |
| .mom | Managed Object Model | Average |
| .mpr | FoxPro Generated Menu Program | Average |
| .mrt | Stimulsoft Report File | Average |
| .msp | MaxScript Page File | Average |
| .mss | Microprocessor Software Specification File | Average |
| .mv | MivaScript File | Average |
| .mvx | Multimedia Fusion Movement Extension | Uncommon |
| .mxml | Flex MXML Component | Average |
| .myapp | Visual Studio Application XML File | Average |
| .nbc | Next Byte Codes Source Code File | Average |
| .ncb | Visual C++ IntelliSense Database | Average |
| .ned | OMNeT++ Network Description File | Average |
| .nib | Interface Resources | Common |
| .nqc | Not Quite C Source Code File | Average |
| .nsh | NSIS Header File | Average |
| .nsi | NSIS Script | Average |
| .nxc | Not eXactly C Source Code File | Average |
| .o | Compiled Object File | Average |
| .oca | Custom Control Library Type File | Average |
| .octest | Xcode Objective-C Unit Test Bundle | Average |
| .ocx | ActiveX Control | Common |
| .omo | OMake Object File | Average |
| .orderedtest | Visual Studio Ordered Test File | Uncommon |
| .os | ObjectScript Source File | Uncommon |
| .ow | Free Pascal 1.0.x Object File | Rare |
| .owl | OWL Source Code File | Average |
| .oxygene | Oxygene Project File | Uncommon |
| .p | Python Pickle File | Uncommon |
| .p | Pascal Source Code | Average |
| .p6 | Perl 6 Source Code File | Uncommon |
| .pas | Pascal Source File | Common |
| .pb | PureBasic Source File | Average |
| .pbg | Pixel Bender Graph File | Average |
| .pbj | Pixel Bender Bytecode File | Common |
| .pbk | Pixel Bender Kernel File | Average |
| .pbproj | Project Builder Project | Uncommon |
| .pbxbtree | Xcode Auto-Complete File | Average |
| .pbxproj | Xcode Project Data File | Common |
| .pbxuser | Xcode Project User Data File | Common |
| .pch | Precompiled Header File | Common |
| .pcp | Windows Installer Patch Creation Properties File | Average |
| .pde | Processing Development Environment Source Code File | Average |
| .pde | Arduino Sketch | Uncommon |
| .pdl | Perl Data Language File | Uncommon |
| .pdm | VB Project Information File | Average |
| .pfg | jEEPers Program Configuration File | Uncommon |
| .ph | Perl Header File | Average |
| .pl | Prolog Source Code File | Average |
| .pl | Perl Script | Very Common |
| .pl1 | PL/I Source Code | Average |
| .plc | PL/B Source File | Average |
| .ple | Messenger Plus! Live Encrypted Log File | Average |
| .plg | Visual Studio Build Log File | Uncommon |
| .pli | PL/I Source Code File | Average |
| .pm | Perl Module | Average |
| .pnt | Panther Project | Rare |
| .po | Portable Object | Average |
| .pod | Perl POD File | Common |
| .pom | Maven Build File | Uncommon |
| .pot | Portable Object File | Average |
| .ppc | Mobile Data Studio Project File | Average |
| .ppl | Free Pascal Dynamic Library | Uncommon |
| .ppu | Free Pascal Unit File | Uncommon |
| .prg | RAPID Program File | Average |
| .prg | Visual FoxPro Program File | Average |
| .prg | RPG Toolkit Program File | Uncommon |
| .prg | xBase Program File | Rare |
| .pri | Windows Compiled Resources File | Average |
| .pri | Qt Project Include File | Average |
| .pro | Qt Project File | Common |
| .psd1 | Windows PowerShell Data File | Uncommon |
| .psess | Visual Studio Performance Session File | Uncommon |
| .psm1 | Windows PowerShell Script Module File | Common |
| .ptl | Rational Rose Petal File | Average |
| .pty | Rational Property Set | Rare |
| .pwn | Pawn Source Code File | Average |
| .py | Python Script | Very Common |
| .pyd | Python Dynamic Module | Average |
| .pym | PYM Macro Preprocessor File | Uncommon |
| .pyw | Python GUI Source File | Average |
| .qpr | FoxPro Generated Query Program | Average |
| .qx | Quexal Source Code | Uncommon |
| .r | R Script File | Average |
| .r | Rez Source Code File | Common |
| .r | Ratfor Source Code File | Uncommon |
| .r | REBOL Script | Average |
| .rav | Rave Reports Project File | Average |
| .rb | Real Studio Project | Uncommon |
| .rb | Ruby Source Code | Common |
| .rbc | Rembo-C Script | Average |
| .rbp | Real Studio Project File | Average |
| .rbvcp | Real Studio Version Controlled Project | Rare |
| .rbxs | ROBLOX Script | Uncommon |
| .rc | Resource Script | Average |
| .rdlc | Visual Studio Client Report Definition File | Average |
| .reb | REBOL Script File | Uncommon |
| .res | C++ Complied Resource Script | Average |
| .res | Windows Resource File | Average |
| .resources | Visual Studio Resource File | Average |
| .resw | Windows Resources File | Average |
| .resx | .NET Managed Resources File | Common |
| .rise | RISE Editor Model File | Average |
| .rnc | RELAX NG Compact Syntax File | Average |
| .rodl | RemObjects Definition Language File | Average |
| .rotest | RemObjects SDK Test File | Uncommon |
| .rotestresult | RemObjects SDK Test Results File | Uncommon |
| .rpy | Python Script | Average |
| .rsrc | Macintosh Resource File | Average |
| .rss | Symbian Application Resource File | Average |
| .ru | Java Russian Font Properties File | Rare |
| .rul | InstallShield Rules File | Average |
| .s | Source Code File | Average |
| .s19 | Motorola S19 File Record | Average |
| .sas | SAS Program File | Average |
| .sb | Small Basic Source Code File | Uncommon |
| .sb | Scratch Project File | Average |
| .sbproj | OpenGL Shader Builder Project | Average |
| .sbr | Visual Studio Source Browser Intermediate File | Uncommon |
| .sc | SuperCollider Source Code File | Average |
| .scc | SourceSafe Source Code Control File | Average |
| .sdef | AppleScript Dictionary Document | Common |
| .sed | Sed Script | Uncommon |
| .sh | Bash Shell Script | Common |
| .sjava | Synchronous Java File | Rare |
| .sll | Static Link Library | Uncommon |
| .sln | Visual Studio Solution File | Common |
| .sma | AMX Mod Plugin Source File | Average |
| .snippet | Visual Studio IntelliSense Code Snippet | Average |
| .so | Shared Library | Average |
| .spt | Cypress Semiconductor Script | Uncommon |
| .spt | ESPL Programming File | Uncommon |
| .src | Source Code | Common |
| .ssc | SourceSafe Status File | Average |
| .ssi | Adobe Dreamweaver Server Side Include File | Average |
| .sud | Super Project Analyzer File | Average |
| .suo | Visual Studio Solution User Options File | Average |
| .sup | Super Project Definition File | Average |
| .svn-base | Subversion Base File | Average |
| .swc | Flex Components Archive | Average |
| .swd | Flash Debug File | Average |
| .sym | Symbols File | Average |
| .t | Turing Source Code File | Average |
| .targets | MSBuild Targets File | Average |
| .tcc | C++ Source Code File | Uncommon |
| .tcl | Tcl Script | Average |
| .tds | Turbo Debugger Symbols File | Average |
| .testrunconfig | Visual Studio Test Run Configuration File | Average |
| .testsettings | Visual Studio Test Settings File | Average |
| .textfactory | BBEdit Text Factory | Average |
| .tiprogram | TI-Basic Program File | Uncommon |
| .tk | Tk Script | Average |
| .tld | Tag Library Descriptor File | Average |
| .tlh | Typelib Generated C/C++ Header File | Average |
| .tli | Typelib Generated C/C++ Inline File | Average |
| .tmlanguage | TextMate Language Grammar File | Average |
| .tmproj | TextMate Project File | Average |
| .tmproject | TextMate Project | Uncommon |
| .tpu | Turbo Pascal Unit | Average |
| .tpx | Turbo Pascal 7 Unit | Average |
| .trx | Visual Studio Test Results File | Common |
| .tt | Visual Studio Text Template | Average |
| .tu | Turing Source File | Average |
| .tur | Turing Program Source File | Average |
| .ui | User Interface File | Average |
| .uml | UML Data Object Model | Average |
| .umlclass | UML Class Model | Uncommon |
| .v | Coq Source Code File | Average |
| .v | Verilog Source Code File | Common |
| .vac | Oc2.316s Cakit File | Rare |
| .var | Variable Data | Uncommon |
| .vbg | Visual Basic Project Group File | Average |
| .vbp | Visual Basic Project File | Average |
| .vbproj | Visual Studio Visual Basic Project | Common |
| .vbx | Visual Basic Custom Control | Average |
| .vbz | Visual Basic Project Template | Average |
| .vc | Verge Code File | Average |
| .vc4 | Visual C++ 4 File | Uncommon |
| .vcp | eMbedded Visual C++ Project File | Average |
| .vcproj | Visual C++ Project File | Common |
| .vcx | Visual Fox Pro Class Library | Average |
| .vcxproj | Visual C++ Project | Common |
| .vdm | VDM Specification File | Average |
| .vdm | VEDIT Macro File | Uncommon |
| .vdp | Visual Studio Deployment Project | Average |
| .vdproj | Visual Studio Setup and Deployment Project | Common |
| .vgc | ViziGen Code Generation Template | Average |
| .vhd | VHDL Source File | Average |
| .vic | ViziGen Code Import Mappings File | Uncommon |
| .vm | Velocity Template | Average |
| .vpc | ViziGen Configuration File | Uncommon |
| .vsl | Velocity Template File | Uncommon |
| .vsmacros | Visual Studio Binary Macro Project | Average |
| .vsmdi | Visual Studio Test Metadata File | Average |
| .vsmproj | Visual Studio Text Macro Project | Average |
| .vsp | Visual Studio Performance Report File | Average |
| .vspf | Visual Studio Performance Filter File | Uncommon |
| .vsps | Visual Studio Serialized Performance Report | Average |
| .vspscc | Visual Studio Project Source Control File | Average |
| .vspx | Visual Studio Performance Report Data File | Average |
| .vssscc | Visual Studio Solution Source Control File | Average |
| .vtm | Visual Tool Markup Language Document | Common |
| .vtml | Visual Tool Markup Language File | Average |
| .vtv | Adobe Dreamweaver Validator Configuration File | Average |
| .w | OpenEdge Architect Source Code File | Average |
| .w32 | Win32 Makefile | Average |
| .wdgt | Adobe Captivate Widget File | Average |
| .wdgtproj | Dashcode Widget Project | Average |
| .wdl | World Definition Language Script | Average |
| .wid | Visual Studio Widget File | Uncommon |
| .worksheet | BBEdit Shell Worksheet File | Uncommon |
| .workspace | Code::Blocks Workspace File | Average |
| .wowproj | AddOn Studio Project File | Uncommon |
| .wsc | Windows Script Component | Average |
| .wsp | SharePoint Solution Package | Average |
| .x | Lex Source Code File | Rare |
| .xaml | XAML File | Average |
| .xap | XACT Project | Average |
| .xcode | Xcode Project | Uncommon |
| .xcodeproj | Xcode Project | Common |
| .xcsnapshots | Xcode Snapshot | Average |
| .xcworkspace | Xcode Workspace File | Average |
| .xib | Interface Builder File | Average |
| .xoml | Windows Workflow File | Average |
| .xq | XQuery File | Common |
| .xql | XML Query Language File | Average |
| .xqm | XQuery Module | Average |
| .xquery | XQuery Source Code File | Average |
| .xqy | XQuery Source File | Uncommon |
| .xsd | XML Schema Definition | Common |
| .xsx | Visual Studio XML Schema Layout File | Uncommon |
| .xt | Xdebug Trace File | Average |
| .y | Yacc Source File | Average |
| .yab | Yabasic Source Code | Uncommon |
| .yml2 | YML Script | Rare |
| .ymp | YaST Metapackage File | Average |
| .ypr | BYOB Project File | Average |