What are data files and how do I open a data file?
| File Type | Category | File Format | |
|---|---|---|---|
| .1pe | Data Files | TurboTax Form File | |
| .1ph | Data Files | TurboTax File | |
| .3dr | Data Files | 3DMark Results File | |
| .3dt | Data Files | 3D Topicscape File | |
| .3me | Data Files | TurboTax Form File | |
| .3pe | Data Files | TurboTax 2008 Form File | |
| .8xg | Data Files | TI-83/84 Plus Group File | |
| .8xk | Data Files | TI-83 Plus Application Upgrade File | |
| .8xs | Data Files | TI-83/84 Plus String File | |
| .8xv | Data Files | TI-83/84 Plus Variable File | |
| .WNF | Data Files | InfoSelect Data File | |
| .a3l | Data Files | Authorware 3 Library | |
| .a3m | Data Files | Authorware 3 Macintosh File | |
| .a3w | Data Files | Authorware 3 Windows File | |
| .a4l | Data Files | Authorware 4 Library | |
| .a4m | Data Files | Authorware 4 Macintosh File | |
| .a4w | Data Files | Authorware 4 Windows File | |
| .a5l | Data Files | Authorware 5 Library | |
| .a65 | Data Files | Authorware 6.5 File | |
| .aam | Data Files | Authorware Map File | |
| .ab1 | Data Files | DNA Electropherogram File | |
| .ab2 | Data Files | Print Shop Address Book File | |
| .ab3 | Data Files | PhotoImpact 3 Album File | |
| .abcd | Data Files | AudioVisual Book Data File | |
| .abdata | Data Files | Adobe Bridge Data File | |
| .abi | Data Files | DNA Chromatogram File | |
| .abkprj | Data Files | Ashampoo Backup Project | |
| .abp | Data Files | AVS Barcode Profile | |
| .abs | Data Files | Absolute Database File | |
| .aby | Data Files | AOL Address Book File | |
| .aca | Data Files | Agent Character Animation File | |
| .acc | Data Files | Graphics Accounts Data File | |
| .acf | Data Files | Agent Character Data File | |
| .acg | Data Files | Agent Preview File | |
| .adf | Data Files | ESRI ArcInfo Binary Grid Format | |
| .adt | Data Files | ACT! Document Template | |
| .adu | Data Files | Addict User Dictionary File | |
| .afe | Data Files | Avid File Exchange File | |
| .aft | Data Files | Ancestry.com Family Tree Database | |
| .agd | Data Files | AgileGraph Data File | |
| .aggr | Data Files | Adobe Captivate Aggregate File | |
| .aifb | Data Files | AIF Builder Project File | |
| .ais | Data Files | HP NewWave Cardfile Application Data File | |
| .aiv | Data Files | AIVault Data File | |
| .ald | Data Files | Dynamics AX Application Label Data File | |
| .alf | Data Files | ACT! Lookup File | |
| .amb | Data Files | AIMMS Model File | |
| .amsorm | Data Files | OnLine Ringman Auction Client File | |
| .amu | Data Files | PictureGear Studio Photo Album File | |
| .an1 | Data Files | Street Atlas USA Draw File | |
| .anme | Data Files | Anime Studio Document | |
| .anx | Data Files | HotDocs Answer File | |
| .aph | Data Files | Ability Album File | |
| .ashprj | Data Files | Ashampoo Burning Studio Project | |
| .asnd | Data Files | Adobe Sound Document | |
| .atf | Data Files | Axon Text File | |
| .ats | Data Files | Advanced ETL Transformation Script | |
| .avc | Data Files | Kaspersky Virus Database | |
| .avj | Data Files | AntiVir Job File | |
| .aw | Data Files | Answer Wizard File | |
| .awdb | Data Files | Access Walker Database File | |
| .awg | Data Files | Activeworlds Object Group File | |
| .azz | Data Files | AZZ Cardfile Database File | |
| .bafl | Data Files | BurnAware File List | |
| .bcc | Data Files | Calendar Creator File | |
| .bci | Data Files | Belarc Advisor Report File | |
| .bcm | Data Files | Business Contact Manager File | |
| .bct | Data Files | Adobe Bridge Thumbnail Cache File | |
| .bdc | Data Files | Babylon Dictionary File | |
| .bdic | Data Files | Chrome Dictionary File | |
| .bfx | Data Files | Bitware Fax Document | |
| .bgt | Data Files | Graphics Accounts Data File | |
| .bim | Data Files | Bytessence InstallMaker Document | |
| .bld | Data Files | Envisioneer Building Project File | |
| .blg | Data Files | Windows Binary Performance Log File | |
| .bln | Data Files | Golden Software Blanking File | |
| .bok | Data Files | TestGen Testbank File | |
| .box | Data Files | E-mail Mailbox | |
| .brain | Data Files | PersonalBrain Mind Map File | |
| .brd | Data Files | EAGLE Circuit Board File | |
| .brw | Data Files | Calyx Point Borrower File | |
| .btf | Data Files | NationsBank Check Images | |
| .btif | Data Files | NationsBank Check Image File | |
| .btinstall | Data Files | uTorrent Installer File | |
| .btm | Data Files | BizTalk Map File | |
| .bvp | Data Files | VodaHost BlueVoda Project File | |
| .cav | Data Files | Comodo Virus Definitions File | |
| .cca | Data Files | Multimedia Fusion File | |
| .ccp | Data Files | RIB Import Converter Profile | |
| .ccr | Data Files | ASTM Continuity of Care Record | |
| .cdpx | Data Files | ConceptDraw PROJECT XML File | |
| .cdpz | Data Files | ConceptDraw PROJECT Document | |
| .cgf | Data Files | Crytek Geometry Format File | |
| .chn | Data Files | Ethnograph Data | |
| .ckt | Data Files | CircuitMaker File | |
| .cl2 | Data Files | HY-TEK Meet Results File | |
| .cl4 | Data Files | Easy CD Creator 4 Project File | |
| .clix | Data Files | CLIX Command File | |
| .clm | Data Files | MagicJack Call Log File | |
| .clp | Data Files | Windows Clipboard File | |
| .clx | Data Files | Standard Dictionary File | |
| .cmap | Data Files | CmapTools Concept Map File | |
| .cmbl | Data Files | Logger Pro Data File | |
| .cml | Data Files | Chemical Markup Language File | |
| .cms | Data Files | Connection Manager Service Profile | |
| .cn1 | Data Files | CNR Modem Initialization Data File | |
| .cna | Data Files | Catena Project File | |
| .cpf | Data Files | Cognos Project File | |
| .cpmz | Data Files | Miradi/ConPro Project File | |
| .cptl | Data Files | Adobe Captivate Project Template File | |
| .cptx | Data Files | Adobe Captivate Project File | |
| .crev | Data Files | Adobe Captivate Commentable SWF File | |
| .crtx | Data Files | Office 2007 Chart Template File | |
| .cry | Data Files | CryENGINE Map File | |
| .csa | Data Files | PNA Code Calset File | |
| .csv | Data Files | Comma Separated Values File | |
| .ctm | Data Files | CrazyTalk Model File | |
| .ctt | Data Files | Messenger Contact List | |
| .ctv | Data Files | Citavi Project | |
| .ctv3 | Data Files | Citavi 3 Project File | |
| .cub | Data Files | Analysis Services Cube File | |
| .cursorfx | Data Files | CursorFX Theme File | |
| .cvd | Data Files | ClamAV Virus Definitions File | |
| .cvn | Data Files | CineVision Encoding Session | |
| .cwk | Data Files | ClarisWorks Document | |
| .cwz | Data Files | Circuit Wizard File | |
| .cyo | Data Files | Clustify Output File | |
| .d01 | Data Files | VirtualDrive Disc Image Part 2 File | |
| .da2 | Data Files | DeepAnalysis Save File | |
| .daf | Data Files | Digital Anchor File | |
| .dam | Data Files | DeltaMaster Analysis Model | |
| .das | Data Files | DeltaMaster Analysis Session | |
| .dat | Data Files | Data File | |
| .db- | Data Files | Norton Nprotect Database File | |
| .dbd | Data Files | DemoShield Project | |
| .dbgsym | Data Files | Debug Symbols File | |
| .dcmd | Data Files | DiskCatalogMaker Thumbnail-Enabled Catalog | |
| .dcmf | Data Files | DiskCatalogMaker Catalog | |
| .dcpf | Data Files | Disc Copier Project File | |
| .dcpr | Data Files | Adobe DNG Camera Profile Recipe File | |
| .ddb | Data Files | Digidesign Database | |
| .ddc | Data Files | DivX Descriptor File | |
| .ddcx | Data Files | DivX Descriptor 2 File | |
| .dfproj | Data Files | DVD Flick Project | |
| .dhcd | Data Files | DHCD Computing Application Data File | |
| .dif | Data Files | Data Interchange Format | |
| .dii | Data Files | Summation Batch Load File | |
| .dita | Data Files | DITA Document | |
| .ditamap | Data Files | DITA Topic Map File | |
| .ditaval | Data Files | DITA Conditions File | |
| .djm | Data Files | Dynojet Map File | |
| .dm2 | Data Files | Toad Data Modeler 2 File | |
| .dmc | Data Files | Datamartist Data Canvas File | |
| .dmsk | Data Files | DivX Temporary Video Data File | |
| .dmsp | Data Files | PhotoSuite Project File | |
| .dockzip | Data Files | ObjectDock File | |
| .dpn | Data Files | Depiction Data File | |
| .dpt | Data Files | Kingsoft Presentation Template | |
| .drl | Data Files | Gerber Drill Rack File | |
| .dsb | Data Files | Wondershare DVD Slideshow Builder Project | |
| .dsy | Data Files | Directory Synchronizer Project File | |
| .dsz | Data Files | Orchida (OES) Embroidery File | |
| .dta | Data Files | Chain Engineering Database | |
| .dtr | Data Files | DATroniC Data Recording | |
| .dvdproj | Data Files | iDVD Project File | |
| .dvds | Data Files | DVDStyler Project File | |
| .dwi | Data Files | Dance With Intensity Song File | |
| .dwp | Data Files | DarkWave Studio Project File | |
| .dwz | Data Files | DVD MovieFactory Project File | |
| .dz | Data Files | Dzip File | |
| .eap | Data Files | Enterprise Architect Project | |
| .eas | Data Files | RSLogix Symbol File | |
| .ebuild | Data Files | Portage eBuild Script | |
| .ec0 | Data Files | MetroCount Traffic Data File | |
| .ecc | Data Files | dvdisaster Error Correction File | |
| .ecl | Data Files | Management-Ware Mass Mailing News E-Campaign List | |
| .ecm | Data Files | ECM Disc Image | |
| .edat | Data Files | E-DataAid 1.x File | |
| .edat2 | Data Files | E-DataAid 2.0 File | |
| .edf | Data Files | ESRF Data File | |
| .edfx | Data Files | Estimator.NET Estimate File | |
| .edg | Data Files | Edge Diagrammer File | |
| .eep | Data Files | EEPROM Data File | |
| .efp | Data Files | Exchange Forms Designer Template | |
| .efx | Data Files | eFax Document | |
| .egp | Data Files | Easy Grade Pro Gradebook File | |
| .emb | Data Files | Wilcom Embroidery Design File | |
| .emlxpart | Data Files | Mail Message Attachment | |
| .emrg | Data Files | E-Merge 1.x Data File | |
| .emrg2 | Data Files | E-Merge 2.0 Data File | |
| .env | Data Files | Adobe Dictionary Data File | |
| .epf | Data Files | Edgecam Educational Part File | |
| .es | Data Files | E-Studio 1.x Experiment File | |
| .es2 | Data Files | E-Studio 2.0 Experiment File | |
| .esb | Data Files | Es-Builder Book File | |
| .ese | Data Files | Millions Email Generator Email List File | |
| .esq | Data Files | Embroidery Sequence File | |
| .esx | Data Files | Xactimate Insurance Claims Estimate | |
| .ett | Data Files | Kingsoft Spreadsheets Template | |
| .ev | Data Files | Echoview File | |
| .ev3 | Data Files | Team Manager Meet Event File | |
| .evy | Data Files | Envoy File | |
| .ews | Data Files | EasyWorship Schedule File | |
| .exif | Data Files | Exchangeable Image Information File | |
| .exl | Data Files | Export Lister File | |
| .exv | Data Files | Adobe Extension Script | |
| .exx | Data Files | IBM Linkway MsgPut File | |
| .fa | Data Files | FASTA Formatted Sequence File | |
| .fasta | Data Files | FASTA Sequence File | |
| .fes | Data Files | Fileless Occurrence Placeholder | |
| .ffd | Data Files | Flat File Descriptor | |
| .ffwp | Data Files | FormsForWeb Packet | |
| .fid | Data Files | File Expander Engine Descriptions Database | |
| .fil | Data Files | Files List Object File | |
| .flame | Data Files | Fractal Flames File | |
| .flk | Data Files | Folder Lock File | |
| .fll | Data Files | FoxPro Dynamic-Link Library | |
| .flo | Data Files | iGrafx FlowCharter File | |
| .flow | Data Files | Expression SketchFlow Data File | |
| .flwa | Data Files | Folder Lock Wallet File | |
| .fnbk | Data Files | Food Network Recipe Manager Data File | |
| .fnrecipes | Data Files | Food Network Recipe File | |
| .fo | Data Files | XSL-FO Form | |
| .folx | Data Files | Folx Download File | |
| .fop | Data Files | InfoZoom Protected Data File | |
| .fox | Data Files | InfoZoom Data File | |
| .fpsl | Data Files | FileMaker Pro Snapshot Link | |
| .frl | Data Files | Electronic Form Loader File | |
| .fro | Data Files | dBASE IV Compiled Report | |
| .fsc | Data Files | Practical Scriptwriter File | |
| .fss | Data Files | Splitty Data Split File | |
| .ftm | Data Files | Family Tree Maker for DOS File | |
| .ftw | Data Files | Family Tree Maker File | |
| .gal | Data Files | GenePix Array List File | |
| .gallery | Data Files | SMART Notebook Gallery File | |
| .galleryco | Data Files | SMART Notebook Gallery Collection File | |
| .galleryit | Data Files | SMART Notebook Gallery Item File | |
| .gan | Data Files | GanttProject Project File | |
| .gbr | Data Files | Gerber File | |
| .gcw | Data Files | Microsoft Mathematics Worksheet | |
| .gcx | Data Files | Grapher Graph File | |
| .ged | Data Files | GEDCOM Genealogy Data File | |
| .gedcom | Data Files | GEDCOM Genealogy File | |
| .gen | Data Files | ArcView ARC/INFO UnGenerate file | |
| .gexf | Data Files | Graph Exchange XML Format File | |
| .ggb | Data Files | GeoGebra Document | |
| .gis | Data Files | CFS Console Game Installer Settings File | |
| .gls | Data Files | Babylon Glossary File | |
| .gms | Data Files | Gesture and Motion Signal File | |
| .gno | Data Files | GenoPro Genealogy Tree File | |
| .gnp | Data Files | GNPeak Output File | |
| .gpi | Data Files | Garmin Point of Interest File | |
| .gpj | Data Files | Grapher Project File | |
| .gpr | Data Files | GenePix Results File | |
| .gra | Data Files | Microsoft Graph File | |
| .grade | Data Files | GradeStat Document | |
| .graphml | Data Files | GraphML File | |
| .graphmlz | Data Files | Zip Compressed GraphML File | |
| .grib | Data Files | Gridded Binary File | |
| .grk | Data Files | Gradekeeper Class Gradebook File | |
| .grr | Data Files | Gradekeeper Class Roster File | |
| .grt | Data Files | Grapher Template | |
| .grv | Data Files | Office Groove File | |
| .gtar | Data Files | GNU Tar Archive | |
| .gtp | Data Files | Guitar Pro File | |
| .gui | Data Files | Dr.Explain Project File | |
| .gwk | Data Files | GraphiCode PCB Job File | |
| .gxl | Data Files | Graph Exchange Language File | |
| .hcc | Data Files | HydroCAD Prefab Chamber Data File | |
| .hce | Data Files | HydroCAD Hydrograph Data File | |
| .hci | Data Files | HydroCAD IDF Data File | |
| .hcl | Data Files | HotDocs Clause Archive | |
| .hcr | Data Files | HydroCAD Rainfall Curve Data File | |
| .hcu | Data Files | Hydrograph Units Definitons File | |
| .hcx | Data Files | ChartXL Chart | |
| .hda | Data Files | HotDocs Auto-Assemble File | |
| .hdf | Data Files | Hierarchical Data Format File | |
| .hdl | Data Files | HotDocs Library File | |
| .hdpmx | Data Files | HotDocs Publisher Mapping XML File | |
| .hdumx | Data Files | HotDocs User Mapping XML File | |
| .hif | Data Files | Quicken Online File | |
| .hkdb | Data Files | Apple iTunes Library File | |
| .hl | Data Files | HeuristicLab Storage File | |
| .hm3 | Data Files | Help & Manual 3 Project | |
| .hml | Data Files | HostMonitor TestList File | |
| .hmt | Data Files | HighMAT File | |
| .hmxp | Data Files | Help & Manual XML Project | |
| .hmxz | Data Files | Help & Manual Compressed Project | |
| .hs2 | Data Files | HyperRESEARCH 2 Study File | |
| .hst | Data Files | History File | |
| .htb | Data Files | Audacity Help File | |
| .htg | Data Files | HackTheGame Mission Pack | |
| .huh | Data Files | HydroCAD Unit Hydrograph Definitions File | |
| .hvc | Data Files | HotDocs Variable Collection File | |
| .hy1 | Data Files | Ventura Publisher Hyphenation File | |
| .hyv | Data Files | Team Manager Meet Event File | |
| .i5z | Data Files | IUCLID 5 Import/Export File | |
| .iba | Data Files | iBooks Author Document | |
| .ibcd | Data Files | InstantBingoCard Document | |
| .ibooks | Data Files | Multi-Touch iBook | |
| .icalevent | Data Files | iCal Event File | |
| .icaltodo | Data Files | iCal To Do File | |
| .ichat | Data Files | iChat Saved Chat Log | |
| .id2 | Data Files | Windows Live Messenger Emoticon File | |
| .ies | Data Files | IES Photometric Data File | |
| .ifaith | Data Files | iFaith SHSH File | |
| .igc | Data Files | Anime List Builder Input File | |
| .ii | Data Files | IconWorkshop Extended Information File | |
| .iif | Data Files | Intuit Interchange Format File | |
| .imr | Data Files | Impromptu Report File | |
| .imt | Data Files | My Time Data File | |
| .incp | Data Files | InCopy CS3 Package File | |
| .inx | Data Files | Compiled Script | |
| .ip | Data Files | IconPackager Theme File | |
| .ipmeta | Data Files | Apple iPhoto Metadata File | |
| .iproject | Data Files | iClone Project File | |
| .irock | Data Files | intelliRock Sensor Data File | |
| .irp | Data Files | Internet Researcher Project File | |
| .irr | Data Files | Brewer Lamp File | |
| .irx | Data Files | Brewer Irradiation File | |
| .is1 | Data Files | M3 Sakura Real-Time Save 1 File | |
| .isf | Data Files | Inspiration Flowchart Document | |
| .ish1 | Data Files | Animation-ish Wiggledoodle-ish Document | |
| .ish2 | Data Files | Animation-ish FlipBook-ish Document | |
| .ish3 | Data Files | Animation-ish Advanced-ish Document | |
| .ite | Data Files | iTunes Extras File | |
| .itlp | Data Files | iTunes LP Album File | |
| .itm | Data Files | iThink Model File | |
| .itmsp | Data Files | iTunes Store Package | |
| .itn | Data Files | TomTom Navigator Itinerary File | |
| .itx | Data Files | ITX Form Template | |
| .iup | Data Files | Fritz Update File | |
| .ivs | Data Files | Initialization Vector File | |
| .ivt | Data Files | Beyond 20/20 Table File | |
| .iw | Data Files | Chain Engineering Database File | |
| .ix2 | Data Files | WordPerfect Address Book File | |
| .ixb | Data Files | Ulead Disc Image | |
| .jasper | Data Files | JasperReports Data File | |
| .jbi | Data Files | Motoman Robot Job File | |
| .jdb | Data Files | Symantec Endpoint Protection Update File | |
| .jef | Data Files | Janome Embroidery Format | |
| .jmp | Data Files | JMP Data File | |
| .joined | Data Files | HJ-Split Data File | |
| .jrprint | Data Files | JasperReports Print File | |
| .jrxml | Data Files | JasperReports Layout File | |
| .jude | Data Files | JUDE Project File | |
| .kap | Data Files | BSB Chart Image File | |
| .kbs | Data Files | Keyboard Script File | |
| .kdbx | Data Files | KeePass Password Database | |
| .kdc | Data Files | Kaspersky Virus Database File | |
| .kid | Data Files | Kidspiration Document | |
| .kismac | Data Files | KisMAC Webservice File | |
| .kpf | Data Files | Komodo Project File | |
| .kpp | Data Files | Kid Pix Presentation | |
| .kpr | Data Files | KPresenter Presentation | |
| .kpx | Data Files | Kid Pix Picture | |
| .kpz | Data Files | Komodo Template File | |
| .kth | Data Files | Keynote Theme | |
| .kvtml | Data Files | KWordQuiz File | |
| .l6t | Data Files | Line 6 Tone File | |
| .ldf | Data Files | SQL Server Transaction Log File | |
| .lix | Data Files | Logos Library System File | |
| .llb | Data Files | LabVIEW Library File | |
| .lms | Data Files | LenMus Score File | |
| .lmx | Data Files | Landmark Exchange File | |
| .loc | Data Files | GPS Location File | |
| .lp7 | Data Files | LP7 Digitally Signed File | |
| .lpdb | Data Files | Librarian Pro Database File | |
| .lrcat | Data Files | Adobe Photoshop Lightroom Catalog File | |
| .lrdata | Data Files | Adobe Photoshop Lightroom Data File | |
| .lsl | Data Files | LightScribe Label | |
| .lsr | Data Files | LANsurveyor Report | |
| .lsu | Data Files | LANsurveyor Map | |
| .lvm | Data Files | LabVIEW Measurement File | |
| .lvw | Data Files | Livewire Document | |
| .lw4 | Data Files | Lightwright File | |
| .ly | Data Files | LilyPond File | |
| .macbin | Data Files | Macbinary Encoded File | |
| .maf | Data Files | Mutation Annotation Format File | |
| .mai | Data Files | Microsoft Mail File | |
| .mat | Data Files | MATLAB MAT-File | |
| .mbd | Data Files | Multimedia Builder Project File | |
| .mbg | Data Files | Mailbag Assistant Mailbox File | |
| .mbl | Data Files | Logger Pro Data File | |
| .mbx | Data Files | Outlook Express Mailbox | |
| .mc1 | Data Files | MedCalc Data File | |
| .mcd | Data Files | Mathcad Document | |
| .mcxe | Data Files | MedicinesComplete Data File | |
| .md8 | Data Files | Mediator Project File | |
| .mdc | Data Files | Multi Dimension Cube File | |
| .mdm | Data Files | HLM Multivariate Data Matrix File | |
| .mdz | Data Files | Access Wizard Template | |
| .meg | Data Files | MEGA Data File | |
| .menc | Data Files | Windows Mobile Encrypted File | |
| .merlin2 | Data Files | Merlin Project File | |
| .met | Data Files | eMule Resource File | |
| .mex | Data Files | Macro Express File | |
| .mfe | Data Files | MobileFrame Enterprise Data File | |
| .mfp | Data Files | Macromedia FlashPaper Document | |
| .mfu | Data Files | MobileFrame Update File | |
| .mfv | Data Files | MobileFrame Device Pack File | |
| .mindnode | Data Files | MindNode Document | |
| .mission | Data Files | MissionMaker Project File | |
| .mit | Data Files | MineEdit Inventory Template File | |
| .mls | Data Files | Milestones Simplicity File | |
| .mm6 | Data Files | Money Manager 6 File | |
| .mma | Data Files | Master Album Maker Photo Album File | |
| .mmc | Data Files | Microsoft Media Catalog | |
| .mmu | Data Files | myPM Merge Data File | |
| .mmw | Data Files | AceMoney Money File | |
| .mnc | Data Files | My Notes Center Notebook | |
| .mnk | Data Files | My Notes Keeper Notebook | |
| .mno | Data Files | Macromedia Design Note | |
| .mny | Data Files | Microsoft Money File | |
| .moho | Data Files | Anime Studio Animation Project | |
| .mol | Data Files | MDL Molfile | |
| .money | Data Files | Money Data File | |
| .mosaic | Data Files | MacOSaiX Mosaic File | |
| .mox | Data Files | ExtendSim Simulation Software Model | |
| .mpi | Data Files | InstallJammer Project File | |
| .mpj | Data Files | RoboHelp HTML Project | |
| .mpp | Data Files | Microsoft Project File | |
| .mps | Data Files | Mathematical Programming System File | |
| .mpt | Data Files | Microsoft Project Template | |
| .mpx | Data Files | Microsoft Project Exchange File | |
| .mpz | Data Files | Miradi Project File | |
| .mpzip | Data Files | Multisim Pack File | |
| .mq4 | Data Files | MetaTrader Custom Indicator | |
| .ms10 | Data Files | Multisim 10 Circuit Design File | |
| .ms8 | Data Files | Multisim 8 Circuit Design File | |
| .msb | Data Files | Oracle Binary Message File | |
| .mth | Data Files | Derive Math File | |
| .mtt | Data Files | MetadataTouch Template | |
| .mtw | Data Files | Minitab Worksheet File | |
| .muf | Data Files | Alpha Five Licence File | |
| .mup | Data Files | Music Publisher Score | |
| .mw | Data Files | Maple Worksheet | |
| .mwf | Data Files | MapGuide Author Map Window File | |
| .mx | Data Files | Mathematica Serialized Package File | |
| .mxad | Data Files | Mandelbrot Explorer All Data File | |
| .mxc2 | Data Files | MAGIX Cache File | |
| .myi | Data Files | MySQL MyISAM Index File | |
| .nbe | Data Files | Nessus Report File | |
| .nbk | Data Files | SMART Notebook File | |
| .ndb | Data Files | ClamAV Extended Signature File | |
| .ndk | Data Files | Lotus Notes Design Elements File | |
| .ndx | Data Files | dBASE Index File | |
| .nessus | Data Files | Nessus Network Security Scanner File | |
| .net | Data Files | netViz Project File | |
| .neta | Data Files | Netica Binary File | |
| .nfl | Data Files | Nokia Flash Lite Package | |
| .nitf | Data Files | National Imagery Transmission Format File | |
| .nmind | Data Files | NovaMind Mind Map File | |
| .nmp | Data Files | NewsMaker Project File | |
| .nni | Data Files | ANNI Neural Network Investing File | |
| .nnp | Data Files | ANNI Neural Network Portfolio File | |
| .not | Data Files | Notation File | |
| .notebook | Data Files | SMART Notebook File | |
| .np | Data Files | Portfolio NetPublish File | |
| .npl | Data Files | Nokia Playlist File | |
| .npr | Data Files | Nuendo Project File | |
| .npt | Data Files | Portfolio NetPublish Template | |
| .nrb | Data Files | Nero CD-ROM Boot Compilation | |
| .nrc | Data Files | Nero Disc Compilation File | |
| .nrd | Data Files | Nero DVD-Video Compilation File | |
| .nrl | Data Files | Autonomy Interwoven Link File | |
| .nrm | Data Files | Nero Mixed Mode CD Compilation | |
| .nru | Data Files | Nero UDF CD-ROM Compilation | |
| .nsq | Data Files | NScheduler Data File | |
| .nsr | Data Files | Nessus Security Report File | |
| .ntf | Data Files | Lotus Note Template | |
| .ntx | Data Files | Clipper Index File | |
| .nv2 | Data Files | NewViews 2 Database File | |
| .nvdl | Data Files | NVDL Script | |
| .nvl | Data Files | UniChem Results File | |
| .nvram | Data Files | VMware NVRAM File | |
| .nws | Data Files | Windows Live Mail Newsgroup File | |
| .obd | Data Files | Office Binder Document | |
| .od | Data Files | Mascopt Graph Request File | |
| .odx | Data Files | BizTalk Server Orchestration File | |
| .oeaccount | Data Files | Windows Mail Account File | |
| .ofc | Data Files | Open Financial Connectivity File | |
| .ofm | Data Files | OmniForm Form | |
| .oft | Data Files | Outlook File Template | |
| .ofx | Data Files | Open Financial Exchange File | |
| .olk | Data Files | Outlook Address Book File | |
| .olk14cate | Data Files | Outlook Category File | |
| .olk14cont | Data Files | Outlook Contact File | |
| .olk14even | Data Files | Outlook Calendar Event File | |
| .olk14grou | Data Files | Outlook Group File | |
| .olk14mail | Data Files | Outlook Mail Account File | |
| .olk14mess | Data Files | Outlook Message File | |
| .olk14msgs | Data Files | Outlook Email Message Data File | |
| .olk14note | Data Files | Outlook Note File | |
| .olk14sign | Data Files | Outlook Signature File | |
| .olk14task | Data Files | Outlook Task File | |
| .olt | Data Files | Orbit Downloads List | |
| .omcs | Data Files | Office Manager Access File | |
| .omp | Data Files | Office Manager Document Archive | |
| .ond | Data Files | Lotus Notes Encapsulated Memo File | |
| .one | Data Files | OneNote Document | |
| .oo3 | Data Files | OmniOutliner 3 File | |
| .opx | Data Files | OrgPlus Org Chart | |
| .or2 | Data Files | Lotus Organizer 2 File | |
| .or3 | Data Files | IBM Lotus Organizer 97 File | |
| .or4 | Data Files | IBM Lotus Organizer 97 GS File | |
| .or5 | Data Files | Lotus Organizer 5 File | |
| .or6 | Data Files | Lotus Organizer 6 File | |
| .org | Data Files | Lotus Organizer File | |
| .otl | Data Files | NoteTab Outline File | |
| .otln | Data Files | Opal Outline File | |
| .otp | Data Files | OpenDocument Presentation Template | |
| .out | Data Files | Output File | |
| .ova | Data Files | Open Virtual Appliance | |
| .ovf | Data Files | Open Virtualization File | |
| .p3 | Data Files | Primavera P3 Project File | |
| .pab | Data Files | Personal Address Book | |
| .paf | Data Files | Personal Ancestral File | |
| .pbk | Data Files | Dial-Up Phone Book File | |
| .pcap | Data Files | Packet Capture Data | |
| .pcb | Data Files | Printed Circuit Board Design File | |
| .pcr | Data Files | PCMark Vantage Benchmark File | |
| .pd4 | Data Files | Windows Live Photo Gallery Information File | |
| .pd5 | Data Files | Windows Live Photo Gallery Information File | |
| .pdas | Data Files | PDAStore Data Store File | |
| .pdb | Data Files | Protein Data Bank File | |
| .pdfig | Data Files | PDF Index Generator Project File | |
| .pdx | Data Files | Adobe Acrobat Index File | |
| .peb | Data Files | ProEST+ Buildings File | |
| .pec | Data Files | Brother Embroidery File | |
| .pep | Data Files | TurboProject Project File | |
| .pex | Data Files | Merak Peep Data File | |
| .pf | Data Files | Windows Prefetcher File | |
| .pfc | Data Files | AOL Personal File Cabinet | |
| .pgpf | Data Files | Password Generator Password File | |
| .phb | Data Files | Motorola Phone Book File | |
| .phd | Data Files | PhotoDirector Project File | |
| .phm | Data Files | Pro Home Manager Data File | |
| .pi | Data Files | Pi Calculation Data File | |
| .pis | Data Files | PS2DIS Project File | |
| .pka | Data Files | Packet Tracer Activity File | |
| .pkb | Data Files | Oracle Package Body File | |
| .pkh | Data Files | Oracle Package File | |
| .pks | Data Files | Oracle Package Spec File | |
| .pkt | Data Files | Packet Tracer Network Simulation Model | |
| .plw | Data Files | PicoLog Data File | |
| .pml | Data Files | Process Monitor Log File | |
| .pmm | Data Files | Pegasus Mail Mailbox File | |
| .pmo | Data Files | Broderbund Print Meta Object File | |
| .pmr | Data Files | Avid Persisent Media Record File | |
| .poi | Data Files | Magellan Maestro Point of Interest File | |
| .por | Data Files | SPSS Portable File | |
| .pos | Data Files | Trimble Position File | |
| .postal | Data Files | TomTom Postal Code File | |
| .pot | Data Files | PowerPoint Template | |
| .potm | Data Files | PowerPoint Open XML Macro-Enabled Presentation Template | |
| .potx | Data Files | PowerPoint Open XML Presentation Template | |
| .pp | Data Files | Pocket Physics Sketch File | |
| .ppr | Data Files | Project Planner Reader File | |
| .ppsm | Data Files | PowerPoint Open XML Macro-Enabled Slide Show | |
| .pptm | Data Files | PowerPoint Open XML Macro-Enabled Presentation | |
| .prb | Data Files | xyAlgebra Probabilities File | |
| .pre | Data Files | Lotus Freelance Graphics File | |
| .prj | Data Files | Project File | |
| .pro4 | Data Files | ProPresenter 4 Document | |
| .pro4pl | Data Files | ProPresenter Playlist File | |
| .pro4plx | Data Files | ProPresenter Playlist Bundle | |
| .pro4x | Data Files | ProPresenter 4 Bundle File | |
| .prp | Data Files | Rational Model Properties File | |
| .prs | Data Files | Harvard Graphics Presentation | |
| .prz | Data Files | Freelance Graphics Presentation File | |
| .psa | Data Files | Photoshop Album Catalog File | |
| .ptb | Data Files | Power Tab File | |
| .ptk | Data Files | Quicken Online Financial Data File | |
| .ptn | Data Files | PaperPort Thumbnail File | |
| .ptz | Data Files | E-Transcript Bundle File | |
| .pvl | Data Files | Instalit Library | |
| .pxa | Data Files | XpressAccounts Data File | |
| .pxc | Data Files | Photodex Cache File | |
| .pxf | Data Files | Transit XV Pack Project File | |
| .pxj | Data Files | RecordNow Project | |
| .q07 | Data Files | QuickTax 2007 Tax Return | |
| .q08 | Data Files | QuickTax 2008 Tax Return | |
| .q09 | Data Files | QuickTax 2009 Tax Return | |
| .q3d | Data Files | Quest3D Project File | |
| .qb2005 | Data Files | QuickBooks 2005 File | |
| .qb2006 | Data Files | QuickBooks 2006 File | |
| .qb2007 | Data Files | QuickBooks 2007 File | |
| .qb2009 | Data Files | QuickBooks 2009 File | |
| .qb2010 | Data Files | QuickBooks 2010 File | |
| .qb2011 | Data Files | QuickBooks 2011 File | |
| .qb2012 | Data Files | QuickBooks 2012 File | |
| .qbw | Data Files | QuickBooks Data File | |
| .qdat | Data Files | QuickTime Install Cache File | |
| .qdfm | Data Files | Quicken Data File (Macintosh) | |
| .qel | Data Files | Quicken Electronic Library | |
| .qfx | Data Files | Quicken Financial Exchange File | |
| .qif | Data Files | Quicken Interchange Format File | |
| .qm | Data Files | Qt Compiled Translation Source File | |
| .qpb | Data Files | QuickBooks Point of Sale Data File | |
| .qpf | Data Files | Quartus II Project File | |
| .qph | Data Files | Quicken Price History File | |
| .qrp | Data Files | QuickReport File | |
| .qsd | Data Files | Quicken Data File | |
| .qvd | Data Files | QlikView Data File | |
| .qvp | Data Files | ViewletBuilder Project File | |
| .qvw | Data Files | QlikView Document | |
| .ral | Data Files | WinRail Track Design File | |
| .rbt | Data Files | Lego MINDSTORMS NXT Program | |
| .rcg | Data Files | Recog Character Recognition Set | |
| .rcx | Data Files | REDCINE-X Project File | |
| .rda | Data Files | R Data File | |
| .rdb | Data Files | N64 ROM Database | |
| .rdx | Data Files | Reflex Data File | |
| .ref | Data Files | Microsoft Train Simulator Reference File | |
| .reference | Data Files | Budget In Brief Reference File | |
| .rel | Data Files | Norton Internet Security Log File | |
| .ret | Data Files | BusinessObjects Template | |
| .rf1 | Data Files | Retirement Forecast File | |
| .rfa | Data Files | Revit Family File | |
| .rfo | Data Files | RoboForm Option File | |
| .rge | Data Files | Entourage File Archive | |
| .rgmc | Data Files | RootsMagic Genealogy Project File | |
| .rgo | Data Files | RepliGo File | |
| .rl | Data Files | R.viewer List File | |
| .rmuf | Data Files | Alpha Five Runtime License File | |
| .rnq | Data Files | Renque Model File | |
| .roca | Data Files | RIB office Compressed Archive | |
| .rod | Data Files | Actuate Report Object Design File | |
| .rog | Data Files | Roger 2 Input Data File | |
| .roi | Data Files | Report Object Instance | |
| .rou | Data Files | Gerber Route File | |
| .rox | Data Files | Roxio Project File | |
| .roxio | Data Files | Roxio Project | |
| .rp | Data Files | Axure RP Project File | |
| .rpa | Data Files | RIB Project Archive File | |
| .rpd | Data Files | Roleplay Designer Data File | |
| .rpprj | Data Files | Axure RP Shared Project File | |
| .rpprj | Data Files | Reaper Project File | |
| .rpt | Data Files | Crystal Reports File | |
| .rrt | Data Files | Rhapzode Resource Template | |
| .rsc | Data Files | Symbian Application Compiled Resource File | |
| .rsp | Data Files | RSLogix PLC Program File | |
| .rsv | Data Files | RSView32 Project File | |
| .rsw | Data Files | R&R SQL Report Writer Report File | |
| .rtp | Data Files | Gromacs Residue Topology Parameter File | |
| .rvdata | Data Files | RPG Maker VX Data File | |
| .rvt | Data Files | Revit Project File | |
| .rwg | Data Files | Random Word Generator Project File | |
| .rws | Data Files | Retina Wireless Scanner File | |
| .rxdata | Data Files | RMXP Data File | |
| .s85 | Data Files | Sabre Airline Solutions Chart | |
| .sam | Data Files | Ami Pro Document | |
| .sam07 | Data Files | SAM 2007 Package | |
| .sar | Data Files | Sibelius Arrange Style | |
| .sbd | Data Files | Office Accounting Company Data File | |
| .sbq | Data Files | Superbase QuickReports File | |
| .sbt | Data Files | Superbase Data Notes File | |
| .sbw | Data Files | US Treasury Savings Bonds Wizard File | |
| .sc45 | Data Files | SuperCard Project File | |
| .sca | Data Files | Norton AntiVirus Scan File | |
| .scd | Data Files | TurboTax Tax Schedule List | |
| .scexcludb | Data Files | Spring Cleaning Exclusions File | |
| .scg | Data Files | myPM SCG Definition File | |
| .schematic | Data Files | MCEdit Schematic File | |
| .screstore | Data Files | Spring Cleaning Restore Log | |
| .scresults | Data Files | Spring Cleaning Results File | |
| .scz | Data Files | SmartDraw Collection Package File | |
| .sdd | Data Files | StarOffice Presentation | |
| .sdq | Data Files | SAS Data File | |
| .sdts | Data Files | USGS Data File | |
| .sel | Data Files | LinkOne Selection List File | |
| .sen | Data Files | SenTest Data File | |
| .seo | Data Files | SEO Note File | |
| .ser | Data Files | GeneMapper Project File | |
| .sgml | Data Files | Standard Generalized Markup Language File | |
| .sgn | Data Files | Slax Boot File | |
| .shc | Data Files | Adobe Photoshop Contours File | |
| .shw | Data Files | Corel Presentation | |
| .sidx | Data Files | StuffIt Archive Index File | |
| .sim | Data Files | SAP Tutor File | |
| .skc | Data Files | SideKick Card File | |
| .skim | Data Files | Skim Notes File | |
| .skv | Data Files | Semicolon Separated Values File | |
| .skx | Data Files | XLANG Schedule File | |
| .sldtm | Data Files | SDL Translation Memory File | |
| .sle | Data Files | Sisulizer Package File | |
| .slk | Data Files | Symbolic Link File | |
| .smm | Data Files | Samsung Memo File | |
| .snag | Data Files | SnagIt Capture File | |
| .sonic | Data Files | DigitalMedia Project File | |
| .soundpack | Data Files | SoundPackager Sound Package | |
| .sp45 | Data Files | SuperCard Player File | |
| .spub | Data Files | Disc Cover File | |
| .stk | Data Files | Stickfigure Animator File | |
| .stm | Data Files | Exchange Streaming Media File | |
| .stproj | Data Files | Samsung Theme Document | |
| .sttpl | Data Files | Samsung Theme Showcase File | |
| .stu | Data Files | Pinnacle Studio Project File | |
| .styk | Data Files | Stykz Stick Figure | |
| .stykz | Data Files | Stykz Animation | |
| .sui | Data Files | StarSplatter User Interface File | |
| .svw | Data Files | SpecView File | |
| .swk | Data Files | StudyWorks Save File | |
| .sxi | Data Files | StarOffice Impress Presentation | |
| .sy3 | Data Files | Harvard Graphics Symbol File | |
| .sylk | Data Files | Microsoft Symbolic Link File | |
| .t01 | Data Files | TaxCut 2001 File | |
| .t02 | Data Files | TaxCut 2002 File | |
| .t03 | Data Files | TaxCut 2003 File | |
| .t04 | Data Files | TaxCut 2004 File | |
| .t05 | Data Files | TaxCut 2005 Tax Return | |
| .t06 | Data Files | TaxCut 2006 Tax Return | |
| .t07 | Data Files | TaxCut 2007 Tax Return | |
| .t08 | Data Files | TaxCut 2008 Tax Return | |
| .t09 | Data Files | At Home 2009 Tax Return | |
| .t10 | Data Files | At Home 2010 Tax Return | |
| .t2 | Data Files | Textease 2000 File | |
| .t2ks | Data Files | Teach2000 Exam Results File | |
| .t2kt | Data Files | Teach2000 Exam File | |
| .tardist | Data Files | TAR Distribution Archive | |
| .tax | Data Files | TurboTax Tax Return | |
| .tax08 | Data Files | TurboTax 2008 Tax Return File | |
| .tax09 | Data Files | TurboTax 2009 Tax Return File | |
| .tax10 | Data Files | TurboTax 2010 Tax Return File | |
| .tax11 | Data Files | TurboTax 2011 Tax Return File | |
| .tax2008 | Data Files | TurboTax 2008 Tax Return | |
| .tax2009 | Data Files | TurboTax 2009 Tax Return | |
| .tax2010 | Data Files | TurboTax 2010 Tax Return | |
| .tax2011 | Data Files | TurboTax 2011 Tax Return | |
| .tb | Data Files | Tabbery Tab File | |
| .tbl | Data Files | StarCraft Information Table | |
| .tcc | Data Files | TimeCalc Classic Data File | |
| .tcx | Data Files | Training Center Database File | |
| .tda | Data Files | Palm To-Do File | |
| .tde | Data Files | Tableau Data Extract File | |
| .tdm | Data Files | LabVIEW Binary Measurement File | |
| .tdt | Data Files | THOR Data Tree File | |
| .te3 | Data Files | WinTrack Object File | |
| .tef | Data Files | TablEdit Tablature | |
| .tet | Data Files | Textease CT Template | |
| .texturepa | Data Files | Minecraft Zip Archive Files | |
| .tfa | Data Files | TreeSoft CashFlow Analysis Data File | |
| .tgf | Data Files | Trivial Graph Format File | |
| .thr | Data Files | Pro/ENGINEER File | |
| .tjp | Data Files | TaskJuggler Project File | |
| .tkfl | Data Files | TKLinks Saver Favorite Links File | |
| .tl5 | Data Files | Timeliner 5 File | |
| .tmr | Data Files | Apimac Timer Document | |
| .tmw | Data Files | Translation Memory Data File | |
| .tmx | Data Files | Translation Memory Exchange File | |
| .to4 | Data Files | Top 4 Compressed Data File | |
| .tol | Data Files | AOL Tool File | |
| .topc | Data Files | TopicCrunch Project File | |
| .tpb | Data Files | GROMACS Binary Input File | |
| .tra | Data Files | WinTrack Railroad Track File | |
| .trd | Data Files | TrID Definitions Package | |
| .trk | Data Files | CompeGPS Land Track File | |
| .trm | Data Files | FTR Media File | |
| .trs | Data Files | Rosetta Stone Language Data File | |
| .tst | Data Files | TestPoint Test File | |
| .tsv | Data Files | Tab Separated Values File | |
| .tt10 | Data Files | TurboTax Canada 2010 Tax Return | |
| .tt11 | Data Files | TurboTax Canada 2011 Tax Return | |
| .ttk | Data Files | Catalyst Translation Toolkit | |
| .twb | Data Files | Tableau Workbook File | |
| .twbx | Data Files | Tableau Packaged Workbook | |
| .txa | Data Files | Midas ViewPoint Text Array List | |
| .txf | Data Files | Tax Exchange Format | |
| .txn | Data Files | MySpaceIM Conversation Log File | |
| .ubj | Data Files | Universal Binary JSON File | |
| .ud | Data Files | OmniPage User Dictionary | |
| .udc | Data Files | Adobe InDesign User Dictionary | |
| .udeb | Data Files | Debian Package File | |
| .uds | Data Files | Sierra Generations File | |
| .uea | Data Files | Protector Suite QL Encrypted Archive | |
| .ulf | Data Files | Universal List File | |
| .ulz | Data Files | USBlyzer Data Capture File | |
| .umf | Data Files | MediaHolder Universal Media Format File | |
| .update | Data Files | ISAPI Update File | |
| .upr | Data Files | Fractal Parameters File | |
| .ustar | Data Files | Uniform Standard Tape Archive Format File | |
| .uvf | Data Files | Uncertain Value Format | |
| .uwl | Data Files | User Word List File | |
| .val | Data Files | Valodas Dictionary File | |
| .vault | Data Files | Fontcase Vault File | |
| .vbpf1 | Data Files | Virtual Business - Personal Finance Data File | |
| .vbw | Data Files | Visual Basic Workspace File | |
| .vcs | Data Files | vCalendar Event File | |
| .vdb | Data Files | Symantec Virus Database File | |
| .vdf | Data Files | AntiVir Virus Definitions File | |
| .vdx | Data Files | Visio Drawing XML File | |
| .vi | Data Files | LabVIEW Virtual Instrument File | |
| .vip | Data Files | Stitch Pattern File | |
| .vle | Data Files | Virtual Labs Electricity Circuit File | |
| .vlg | Data Files | VentaFax Logbook File | |
| .vmsd | Data Files | VMware Snapshot Metadata File | |
| .vmsn | Data Files | VMware Snapshot State File | |
| .vmss | Data Files | VMware Suspended State File | |
| .vmt | Data Files | Valve Material File | |
| .voi | Data Files | VOI Group File | |
| .vok | Data Files | PocketVok Vocabulary File | |
| .voxb | Data Files | Voxler Network File | |
| .vpp | Data Files | Visual Paradigm Project File | |
| .vrd | Data Files | Visio Report Definition File | |
| .vscontent | Data Files | Visual Studio Content File | |
| .vsv | Data Files | Virtual Machine Saved State File | |
| .vsx | Data Files | Visio Stencil XML File | |
| .vtx | Data Files | Visio Template XML File | |
| .vud | Data Files | Virtual Machine Undo Drive File | |
| .vvf | Data Files | Voc Vocabulary File | |
| .vxml | Data Files | VoiceXML File | |
| .wab | Data Files | Windows Address Book | |
| .wcat | Data Files | WinCatalog Collection File | |
| .wcd | Data Files | Works Calendar File | |
| .wcf | Data Files | WebEx Saved Chat Session | |
| .wdf | Data Files | Workshare Compare DeltaFile | |
| .wdq | Data Files | Offline Explorer Queue File | |
| .wea | Data Files | Ecotect Weather File | |
| .wfm | Data Files | Tektronix Waveform Data File | |
| .wid | Data Files | SAP BusinessObjects Web Intelligence File | |
| .windowsli | Data Files | Windows Live Contacts File | |
| .wjr | Data Files | ReGet Deluxe Data File | |
| .wk1 | Data Files | Lotus Worksheet | |
| .wk2 | Data Files | Lotus 2 Worksheet | |
| .wk4 | Data Files | Lotus 4 Worksheet | |
| .wk5 | Data Files | Lotus 5 Worksheet | |
| .wke | Data Files | Lotus 1-2-3 Educational Version Worksheet | |
| .wnk | Data Files | Wink Presentation | |
| .wpc | Data Files | WordPad Converter File | |
| .wpf | Data Files | WordPerfect Form | |
| .wpo | Data Files | HOLUX Waypoint File | |
| .wsi | Data Files | Wise Package Studio Installer Package | |
| .wsm | Data Files | Wise Package Studio Merge Module | |
| .wtb | Data Files | Win-Test Binary Log File | |
| .wtr | Data Files | Encarta File | |
| .xaf | Data Files | Affirm Deposition Transcript | |
| .xappl | Data Files | Spoon XML Application Configuration File | |
| .xas | Data Files | Pro/ENGINEER Assembly Instance Accelerator File | |
| .xbc | Data Files | SMART Notebook File | |
| .xbk | Data Files | SMART Notebook File | |
| .xbt | Data Files | SMART Notebook Template File | |
| .xdb | Data Files | Symantec Virus Database File | |
| .xdp | Data Files | XML Data Package | |
| .xef | Data Files | eManager Form Data | |
| .xem | Data Files | PowerDesigner Model definition File | |
| .xer | Data Files | Primavera P6 Project File | |
| .xfd | Data Files | FormFlow 99 Form Data File | |
| .xfdf | Data Files | Adobe Acrobat XFDF File | |
| .xfo | Data Files | XSL-FO Formatted Form | |
| .xfr | Data Files | iProcess Process Definition File | |
| .xft | Data Files | Adobe Form Designer 5.0 File | |
| .xgml | Data Files | Graph Modeling Language XML File | |
| .xgmml | Data Files | XGMML Graph File | |
| .xlc | Data Files | Excel Chart | |
| .xlf | Data Files | XLIFF Document | |
| .xlgc | Data Files | ExpressK Database File | |
| .xlt | Data Files | Excel Template | |
| .xmcd | Data Files | Mathcad Worksheet File | |
| .xmi | Data Files | XML Metadata Interchange File | |
| .xmpz | Data Files | Miradi XML Project File | |
| .xpdl | Data Files | XPDL Module | |
| .xpg | Data Files | Autoplay Media Studio Exported Page | |
| .xpj | Data Files | RoboHelp HTML Project File | |
| .xpr | Data Files | SyncRO Soft oXygen XML Editor Project | |
| .xpt | Data Files | SAS Transport File | |
| .xrff | Data Files | Extensible Attribute-Relation File Format | |
| .xrp | Data Files | RationalPlan Project File | |
| .xry | Data Files | XRY Data File | |
| .xsl | Data Files | XML Style Sheet | |
| .xsvf | Data Files | Xilinx Serial Vector Format File | |
| .xtg | Data Files | Extensible TreeGraph File | |
| .xtm | Data Files | CmapTools Exported Topic Map | |
| .xvct | Data Files | VISE XML Project File | |
| .xxd | Data Files | Brixx Planner Calendar | |
| .xyz | Data Files | Molecule Specification File | |
| .xyzv | Data Files | Celestia Sampled Trajectory File | |
| .yam | Data Files | Yahoo! Auctions Data | |
| .ychat | Data Files | Yahoo! Messenger Chat Log | |
| .ygf | Data Files | Y Graph Format File | |
| .zdb | Data Files | Quicken Online File | |
| .zdc | Data Files | CD Catalog Expert Database File | |
| .zdct | Data Files | Adobe Language File | |
| .zmc | Data Files | ZoneAlarm Quarantine File |