| Extension |
File Description |
|
Popularity |
| .$er | GroupWise Database | | Average |
| .123 | Lotus 1-2-3 Spreadsheet | | Average |
| .123 | PCB123 Circuit Board Design | | Average |
| .1pe | TurboTax Form File | | Average |
| .1ph | TurboTax File | | Average |
| .3dr | 3DMark Results File | | Average |
| .3dt | 3D Topicscape File | | Average |
| .3me | TurboTax Form File | | Uncommon |
| .3pe | TurboTax 2008 Form File | | Uncommon |
| .4dl | 4th Dimension Database Log File | | Uncommon |
| .4dv | 4D View Ultrasound File | | Average |
| .8xk | TI-83 Plus Application Upgrade File | | Uncommon |
| .a3l | Authorware 3 Library | | Average |
| .a3m | Authorware 3 Macintosh File | | Average |
| .a3w | Authorware 3 Windows File | | Average |
| .a4l | Authorware 4 Library | | Average |
| .a4m | Authorware 4 Macintosh File | | Average |
| .a4w | Authorware 4 Windows File | | Average |
| .a5l | Authorware 5 Library | | Average |
| .a5w | Authorware 5 Windows File | | Average |
| .a65 | Authorware 6.5 File | | Average |
| .aao | Agenda At Once File | | Uncommon |
| .ab | DNA Sequence File | | Average |
| .ab1 | DNA Electropherogram File | | Average |
| .ab2 | Print Shop Address Book File | | Uncommon |
| .ab3 | PhotoImpact 3 Album File | | Average |
| .abcd | AudioVisual Book Data File | | Average |
| .abi | DNA Chromatogram File | | Average |
| .abp | AVS Barcode Profile | | Average |
| .aby | AOL Address Book File | | Average |
| .aca | Agent Character Animation File | | Uncommon |
| .acc | Graphics Accounts Data File | | Average |
| .accdb | Access 2007 Database File | | Very Common |
| .acf | Agent Character Data File | | Uncommon |
| .acg | Agent Preview File | | Uncommon |
| .ade | Access Project Extension | | Average |
| .adp | Access Project | | Average |
| .adt | ACT! Document Template | | Average |
| .adx | Approach Index File | | Average |
| .aft | Ancestry.com Family Tree Database | | Average |
| .agd | AgileGraph Data File | | Uncommon |
| .aifb | AIF Builder Project File | | Average |
| .alc | Dynamics AX Label Description File | | Average |
| .ald | Dynamics AX Application Label Data File | | Average |
| .ali | Dynamics AX Label Index File | | Average |
| .amb | AIMMS Model File | | Average |
| .amsorm | OnLine Ringman Auction Client File | | Average |
| .an1 | Street Atlas USA Draw File | | Uncommon |
| .anme | Anime Studio Project | | Common |
| .apr | ArcView Project File | | Average |
| .arc | Nintendo Archive File | | Rare |
| .arh | ArheoStratigraf Project File | | Rare |
| .ask | askSam Database | | Average |
| .asm | Solid Edge Assembly Document | | Average |
| .ast | ClarisWorks Assistant File | | Uncommon |
| .at5 | Lowrance Map File | | Average |
| .att | Alphacam Lathe Tool File | | Uncommon |
| .aw | Answer Wizard File | | Common |
| .awg | Activeworlds Object Group File | | Average |
| .azw | Amazon Kindle eBook File | | Average |
| .bafl | BurnAware File List | | Uncommon |
| .bci | Belarc Advisor Report File | | Average |
| .bcm | Business Contact Manager File | | Average |
| .bdf | Binary Data File | | Uncommon |
| .bdic | Chrome Dictionary File | | Average |
| .bfx | Bitware Fax Document | | Uncommon |
| .bgl | Babylon Glossary File | | Average |
| .bgt | Graphics Accounts Data File | | Average |
| .bin | Generic Binary File | | Average |
| .bjo | TablEdit Tablature File | | Uncommon |
| .bk | FrameMaker Book File | | Average |
| .bkk | BookBuddi eBook File | | Average |
| .blb | Blob Data File | | Average |
| .bld | Envisioneer Building Project File | | Common |
| .blg | Windows Binary Performance Log File | | Very Common |
| .bok | TestGen Testbank File | | Average |
| .box | E-mail Mailbox | | Average |
| .brd | EAGLE Circuit Board File | | Average |
| .brw | Calyx Point Borrower File | | Average |
| .btf | NationsBank Check Images | | Uncommon |
| .btif | NationsBank Check Image File | | Rare |
| .btm | BizTalk Map File | | Average |
| .btr | Btrieve Database File | | Uncommon |
| .cap | Packet Capture File | | Average |
| .cat | Advanced Disk Catalog Database | | Average |
| .cbg | CyberGauge Data File | | Average |
| .cch | Corel Chart File | | Average |
| .ccr | ASTM Continuity of Care Record | | Average |
| .cct | Director Protected Cast Resource | | Uncommon |
| .cdb | Symbian Phonebook Database | | Average |
| .cdb | Pocket Access Database | | Common |
| .cdb | CardScan Contacts Database | | Average |
| .cdd | ConceptDraw Drawing File | | Common |
| .cdf | Common Data Format | | Uncommon |
| .cdf | Content Definition File | | Common |
| .cdp | CD/Spectrum Pro File | | Uncommon |
| .cdr | Crash Data Retrieval Data File | | Uncommon |
| .cdx | Compound Index File | | Average |
| .cel | Battery 3 Drum Cell File | | Average |
| .celtx | Celtx Project File | | Average |
| .chg | Quicken Online Data File | | Average |
| .chk | InterCheck Checksum Database | | Uncommon |
| .chn | Ethnograph Data | | Average |
| .ckd | Kubotek Design Container | | Uncommon |
| .ckt | CircuitMaker File | | Average |
| .cl2 | HY-TEK Meet Results File | | Uncommon |
| .cl4 | Easy CD Creator 4 Project File | | Uncommon |
| .clb | ICQ Contact List | | Uncommon |
| .clix | CLIX Command File | | Uncommon |
| .clm | GenePattern CEL Descriptor File | | Rare |
| .clm | MagicJack Call Log File | | Average |
| .clp | Windows Clipboard File | | Average |
| .cmbl | Logger Pro Data File | | Uncommon |
| .cna | Catena Project File | | Average |
| .contact | Windows Contact File | | Common |
| .cpi | AVCHD Video Clip Information File | | Common |
| .cpmz | Miradi/ConPro Project File | | Uncommon |
| .crd | Windows Cardfile | | Average |
| .crtx | Office 2007 Chart Template File | | Average |
| .csa | PNA Code Calset File | | Average |
| .csv | Comma Separated Values File | | Very Common |
| .ctf | WhereIsIt Catalog | | Average |
| .ctt | Messenger Contact List | | Average |
| .cursorfx | CursorFX Theme File | | Average |
| .curxptheme | CursorXP Theme File | | Average |
| .cvd | ClamAV Virus Definitions File | | Average |
| .cvn | CineVision Encoding Session | | Average |
| .cwk | ClarisWorks Document | | Average |
| .cws | Claris Works Template | | Average |
| .cwz | Circuit Wizard File | | Uncommon |
| .cxt | Director Protected Cast File | | Rare |
| .cyo | Clustify Output File | | Average |
| .cys | Clustify Summary File | | Average |
| .daf | Digital Anchor File | | Uncommon |
| .dal | DVD-lab Project File | | Average |
| .dam | DeltaMaster Analysis Model | | Average |
| .das | DeltaMaster Analysis Session | | Average |
| .dat | Data File | | Very Common |
| .data | Analysis Studio Offline Data File | | Uncommon |
| .db | Database File | | Very Common |
| .db2 | dBASE II Database | | Average |
| .db3 | SQLite Database File | | Average |
| .dbc | FoxPro Database | | Average |
| .dbd | DemoShield Project | | Average |
| .dbf | Database File | | Average |
| .dbf | FoxPro Table | | Average |
| .dbx | Visual FoxPro Table | | Average |
| .dcf | Document Computation Format | | Common |
| .dcl | DumpSec Report File | | Average |
| .dcm | DiskCatalogMaker Catalog File | | Average |
| .dcmd | DiskCatalogMaker Thumbnail-Enabled Catalog | | Average |
| .ddc | DivX Descriptor File | | Average |
| .ddcx | DivX Descriptor 2 File | | Average |
| .ddt | Diagram Designer Template | | Uncommon |
| .dem | Digital Elevation Model | | Average |
| .des | QuickBooks Forms Template | | Average |
| .dex | DEXIS Digital X-ray File | | Average |
| .dex | Excel Spreadsheet | | Rare |
| .dfm | Midas ViewPoint Display Form | | Average |
| .dfproj | DVD Flick Project | | Average |
| .dft | Solid Edge Draft Document | | Average |
| .dgb | FlashCAD Drawing Database | | Average |
| .dif | Data Interchange Format | | Common |
| .dii | Summation Batch Load File | | Average |
| .dlg | Digital Line Graph | | Average |
| .dm2 | Toad Data Modeler 2 File | | Average |
| .dmo | Derive Demo | | Average |
| .dmo | Movienizer Database File | | Average |
| .dmsk | DivX Temporary Video Data File | | Uncommon |
| .dnc | Dance Database File | | Rare |
| .dockzip | ObjectDock File | | Average |
| .dp1 | DataPower Database File | | Average |
| .dpn | Depiction Data File | | Average |
| .dpx | VASCO DIGIPASS File | | Uncommon |
| .drl | Gerber Drill Rack File | | Average |
| .dsb | Orchida Embroidery File | | Average |
| .dsd | Diet Studio Data File | | Uncommon |
| .dsk | Simple IDs Database | | Average |
| .dsy | Directory Synchronizer Project File | | Average |
| .dsz | Orchida (OES) Embroidery File | | Average |
| .dt0 | DTED Level 0 File | | Average |
| .dt1 | DTED Level 1 File | | Common |
| .dt2 | DTED Level 2 File | | Uncommon |
| .dta | Chain Engineering Database | | Rare |
| .dtr | DATroniC Data Recording | | Average |
| .dvdproj | iDVD Project File | | Average |
| .dvo | Cook'n Cookbook File | | Average |
| .dwi | Dance With Intensity Song File | | Average |
| .e00 | ArcInfo Coverage Export File | | Uncommon |
| .eap | Enterprise Architect Project | | Average |
| .ebuild | Portage eBuild Script | | Average |
| .ec0 | MetroCount Traffic Data File | | Uncommon |
| .eco | ECCO Database File | | Average |
| .ecx | ECCO Corrupted Database File | | Average |
| .edb | Exchange Information Store Database | | Average |
| .edf | Estimator Data File | | Average |
| .edf | ESRF Data File | | Uncommon |
| .eep | EEPROM Data File | | Rare |
| .efx | eFax Document | | Very Common |
| .egp | Easy Grade Pro Gradebook File | | Average |
| .emb | Embroidery Design File | | Average |
| .emb | Everest Embedded Bank File | | Average |
| .emd | ChessBase Tablebase | | Average |
| .emlxpart | Mail Message Attachment | | Average |
| .enc | Electronic Navigation Chart File | | Uncommon |
| .enw | EndNote Citation File | | Uncommon |
| .epp | TalaPhoto Project | | Average |
| .epp | Efficient PPC Project File | | Average |
| .epub | Open eBook File | | Average |
| .epw | EnergyPlus Weather Data File | | Common |
| .er1 | ERWin Entity Relationship Diagram | | Average |
| .esp | ACD/Labs Dataset | | Average |
| .ess | EasySpreadsheet Spreadsheet | | Average |
| .est | Streets & Trips Map File | | Average |
| .est | Construction Cost Estimate File | | Uncommon |
| .esx | Xactimate Insurance Claims Estimate | | Average |
| .et | Easiteach Lesson File | | Uncommon |
| .eta | Google Earth Placemark File | | Uncommon |
| .etd | Adobe Reader EBX Transfer Data File | | Average |
| .etl | Microsoft Event Trace Log File | | Average |
| .ev | Echoview File | | Average |
| .ev3 | Team Manager Meet Event File | | Uncommon |
| .evt | Windows Event Viewer Log File | | Average |
| .evy | Envoy File | | Average |
| .exif | Exchangeable Image Information File | | Common |
| .exp | Export File | | Common |
| .exp | Aurora Expert Trace File | | Average |
| .exx | IBM Linkway MsgPut File | | Average |
| .fa | FASTA Formatted Sequence File | | Average |
| .fasta | FASTA Sequence File | | Average |
| .fbl | iGO Map File | | Uncommon |
| .fcd | First Choice Database | | Average |
| .fcs | First Choice Spreadsheet | | Average |
| .fdb | Portfolio Catalog | | Common |
| .fdb | Art Explosion Catalog | | Average |
| .fdb | Microsoft Dynamics NAV Database File | | Average |
| .ffd | Flat File Description | | Average |
| .ffwp | FormsForWeb Packet | | Average |
| .fhc | FHC Data File | | Average |
| .fid | File Expander Engine Descriptions Database | | Uncommon |
| .fil | Files List Object File | | Average |
| .flame | Fractal Flame File | | Average |
| .fll | FoxPro Dynamic-Link Library | | Average |
| .flo | iGrafx FlowCharter File | | Average |
| .flo | RFFlow Flowchart File | | Average |
| .flp | Activprimary Flipchart File | | Average |
| .flt | Flight Simulator Saved Flight | | Average |
| .fm | FileMaker Spreadsheet | | Average |
| .fm5 | FileMaker 5 Database | | Average |
| .fmp | FileMaker Pro Database | | Average |
| .fo | XSL-FO Form | | Average |
| .fob | Dynamics NAV Object Container File | | Average |
| .fol | PFS First Choice Database File | | Rare |
| .fop | InfoZoom Protected Data File | | Average |
| .fox | InfoZoom Data File | | Average |
| .fp | FileMaker Pro Spreadsheet | | Average |
| .fp3 | FileMaker Pro 3 Database | | Average |
| .fp4 | FileMaker Pro 4 Database | | Average |
| .fp5 | FileMaker Pro 5 Database | | Average |
| .fp7 | FileMaker Pro 7+ Database | | Average |
| .fpsl | FileMaker Pro Snapshot Link | | Average |
| .frl | Electronic Form Loader | | Average |
| .frm | ADL Form | | Average |
| .frm | MySQL Database Format File | | Average |
| .fro | dBASE IV Compiled Report | | Average |
| .frx | FoxPro Report | | Average |
| .fsb | FMOD Sample Bank File | | Average |
| .fsc | Practical Scriptwriter File | | Average |
| .ftm | Family Tree Maker for DOS File | | Average |
| .ftw | Family Tree Maker File | | Average |
| .gan | GanttProject Project File | | Average |
| .gbr | Gerber File | | Average |
| .gc | GraphClick File | | Average |
| .gcx | Grapher Graph File | | Average |
| .gdb | InterBase Database File | | Uncommon |
| .ged | GEDCOM Genealogy Data File | | Average |
| .gedcom | GEDCOM Genealogy File | | Average |
| .gen | ArcView ARC/INFO UnGenerate file | | Uncommon |
| .ggb | GeoGebra Document | | Average |
| .gml | Geography Markup Language File | | Average |
| .gms | Gesture and Motion Signal File | | Average |
| .gno | GenoPro Genealogy Tree File | | Average |
| .gnp | GNPeak Output File | | Rare |
| .gp3 | Guitar Pro 3 File | | Average |
| .gpi | Garmin Point of Interest File | | Common |
| .gps | Survey Pro Coordinate File | | Average |
| .gpx | GPS Exchange File | | Common |
| .gra | Microsoft Graph File | | Average |
| .grade | GradeStat Document | | Average |
| .grf | Generic Graph File | | Average |
| .grf | DPlot Graph File | | Average |
| .grib | Gridded Binary File | | Average |
| .grk | Gradekeeper Class Gradebook File | | Average |
| .grr | Gradekeeper Class Roster File | | Average |
| .grv | Office Groove File | | Average |
| .gs | GemStone Document | | Average |
| .gst | MapInfo Geoset File | | Average |
| .gtp | Guitar Pro File | | Average |
| .gwk | GraphiCode PCB Job File | | Average |
| .gxl | Graph Exchange Language File | | Average |
| .hcc | HydroCAD Prefab Chamber Data File | | Average |
| .hce | HydroCAD Hydrograph Data File | | Average |
| .hci | HydroCAD IDF Data File | | Average |
| .hcp | HydroCAD Project File | | Common |
| .hcr | HydroCAD Rainfall Curve Data File | | Average |
| .hcu | Hydrograph Units Definitons File | | Average |
| .hda | HotDocs Auto-Assemble File | | Average |
| .hdb | HansaWorld Database File | | Average |
| .hdf | Hierarchical Data Format File | | Common |
| .hdi | HotDocs Auto-Install File | | Average |
| .hdl | HotDocs Library | | Average |
| .hif | Quicken Online File | | Average |
| .hl | HeuristicLab Storage File | | Average |
| .hml | HostMonitor TestList File | | Average |
| .hmt | HighMAT File | | Rare |
| .hs2 | HyperRESEARCH 2 Study File | | Average |
| .hsk | Huskey Truss & Building Supply Import File | | Rare |
| .hst | History File | | Average |
| .htg | HackTheGame Mission Pack | | Uncommon |
| .huh | HydroCAD Unit Hydrograph Definitions File | | Average |
| .hyv | Team Manager Meet Event File | | Average |
| .i5z | IUCLID 5 Import/Export File | | Average |
| .ib | InterBase Database | | Average |
| .ics | iCalendar File | | Average |
| .id2 | Windows Live Messenger Emoticon File | | Common |
| .idx | HMI Historical Log Index File | | Average |
| .idx | Navigation POI File | | Average |
| .igc | Anime List Builder Input File | | Average |
| .ihx | IN-HEH Timeline Database | | Average |
| .ii | Axialis IconWorkshop Extended Information File | | Common |
| .iif | Intuit Interchange Format File | | Average |
| .img | Garmin Map File | | Uncommon |
| .imt | My Time Data File | | Average |
| .ink | Mimio Ink Data File | | Uncommon |
| .inp | ABAQUS Input File | | Average |
| .ins | Inspiration File | | Common |
| .ip | IconPackager Theme File | | Average |
| .irock | intelliRock Sensor Data File | | Average |
| .irr | Brewer Lamp File | | Uncommon |
| .irx | Brewer Irradiation File | | Rare |
| .isf | Inspiration Flowchart Document | | Average |
| .itdb | iTunes Database File | | Average |
| .itl | iTunes Library File | | Average |
| .itm | iThink Model File | | Average |
| .itn | TomTom Navigator Itinerary File | | Average |
| .itw | InTouch With Database File | | Average |
| .itx | ITX Form Template | | Average |
| .ivt | Beyond 20/20 Table | | Average |
| .iw | Chain Engineering Database File | | Uncommon |
| .ixb | Ulead Disc Image | | Average |
| .jasper | JasperReports Data File | | Average |
| .jdb | Symantec Endpoint Protection Update File | | Common |
| .jef | Janome Embroidery Format | | Average |
| .jmp | JMP Data File | | Average |
| .jnt | Windows Journal File | | Common |
| .job | MetaCAM Nest Job File | | Common |
| .joboptions | Adobe Joboptions File | | Average |
| .joined | HJ-Split Data File | | Average |
| .jph | JProbe Memory Snapshot | | Average |
| .jrprint | JasperReports Print File | | Common |
| .jrxml | JasperReports Layout File | | Average |
| .jude | JUDE Project File | | Average |
| .kap | BSB Chart Image File | | Average |
| .kdb | Keypass Database File | | Average |
| .kid | Kidspiration Document | | Average |
| .kismac | KisMAC Webservice File | | Average |
| .kmz | Google Earth Placemark File | | Common |
| .kpf | Komodo Project File | | Average |
| .kpp | Kid Pix Presentation | | Average |
| .kpr | KPresenter Presentation | | Average |
| .kpx | Kid Pix Picture | | Average |
| .kpz | Komodo Template File | | Average |
| .l | Game of Life File | | Average |
| .l6t | Line 6 Tone File | | Average |
| .laccdb | Microsoft Access Lock File | | Average |
| .lbl | NiceLabel Template File | | Average |
| .lbx | FoxPro Label File | | Uncommon |
| .lcd | ABBYY Language File | | Average |
| .lcf | ArchiCAD Library Container File | | Average |
| .lcm | Lipikar Custom Map File | | Average |
| .ldif | LDAP Data Interchange Format File | | Average |
| .lex | Adobe Linguistic Library Data File | | Uncommon |
| .lgc | SimpleK Database File | | Average |
| .lgf | PMSCAN Log File | | Uncommon |
| .lgh | HMI Historical Log File | | Average |
| .lgi | Multimedia Logic File | | Average |
| .lgl | Large Graph Layout Edge File | | Rare |
| .lib | Generic Data Library | | Common |
| .lif | TurboTax Information Archive | | Average |
| .livereg | Symantec Antivirus Session File | | Average |
| .liveupdate | Symantec LiveUpdate File | | Common |
| .lix | Logos Library System File | | Average |
| .lix | ExtendSim Simulation Software Library | | Average |
| .llb | LabVIEW Library File | | Average |
| .lms | LenMus Score File | | Average |
| .lmx | Landmark Exchange File | | Average |
| .lnt | LiveNote Case File | | Uncommon |
| .loc | GPS Location File | | Average |
| .lp7 | LP7 Digitally Signed File | | Average |
| .lrf | Sony Portable Reader File | | Average |
| .lrs | Librie Reader Source File | | Average |
| .lrx | Sony Portable Reader File | | Average |
| .lsf | Logos Library System File | | Average |
| .lsl | LightScribe Label | | Average |
| .lsp | LANsurveyor Poll List | | Average |
| .lsr | LANsurveyor Report | | Average |
| .lst | LightScribe Label Template | | Uncommon |
| .lsu | LANsurveyor Map | | Average |
| .lvm | LabVIEW Measurement File | | Average |
| .lw4 | Lightwright File | | Average |
| .ly | LilyPond File | | Average |
| .m | Mathematica Input File | | Common |
| .mag | Magic Circuit Layout | | Average |
| .mai | Microsoft Mail File | | Average |
| .map | Weather Defender Map | | Average |
| .masseffectprofile | Mass Effect Player Profile | | Common |
| .mat | MATLAB MAT-File | | Common |
| .mbb | ManaBook Book File | | Rare |
| .mbf | Microsoft Money Backup File | | Average |
| .mbg | Mailbag Assistant Mailbox File | | Average |
| .mbg | Microsoft Mailbag | | Average |
| .mbl | Logger Pro Data File | | Average |
| .mbp | Mobipocket Notes File | | Average |
| .mbx | Outlook Express Mailbox | | Average |
| .mc1 | MedCalc Data File | | Average |
| .mc9 | Mastercam 9 Geometry File | | Average |
| .mcd | Mathcad Document | | Average |
| .md | Moneydance Financial Data File | | Average |
| .mdb | Microsoft Access Database | | Very Common |
| .mdc | Multi Dimension Cube File | | Average |
| .mdf | Measurement Data Format File | | Average |
| .mdf | SQL Server Database File | | Average |
| .mdl | Simulink Model File | | Average |
| .mdl | Rational Rose Model File | | Average |
| .mdm | HLM Multivariate Data Matrix File | | Average |
| .mdn | Blank Access Database Template | | Average |
| .mdt | Access Database Template | | Average |
| .mdx | Multiple Index File | | Average |
| .mdx | Rational XDE Model File | | Average |
| .mdz | Access Wizard Template | | Average |
| .mem | Mnemosyne Card Collection | | Uncommon |
| .menc | Windows Mobile Encrypted File | | Common |
| .met | eMule Resource File | | Common |
| .mex | Macro Express File | | Average |
| .mfo | Perl ModInfo Descriptor File | | Average |
| .mfp | Macromedia FlashPaper Document | | Average |
| .mgc | MGCSoft Equation Illustrator File | | Average |
| .mls | Milestones Simplicity File | | Average |
| .mm | FreeMind Mind Map | | Average |
| .mmap | MindManager Map File | | Average |
| .mmc | Microsoft Media Catalog | | Average |
| .mmf | Microsoft Message File | | Uncommon |
| .mmp | MindManager Mind Map | | Average |
| .mmp | Master Album Maker Project | | Average |
| .mnc | My Notes Center Notebook | | Average |
| .mng | Yamaha PSR Disk Manager File | | Rare |
| .mnk | My Notes Keeper Notebook | | Average |
| .mno | Macromedia Design Note | | Average |
| .mny | Microsoft Money File | | Average |
| .mobi | Mobipocket eBook | | Average |
| .moho | Anime Studio Animation Project | | Average |
| .mosaic | MacOSaiX Mosaic File | | Average |
| .mox | ExtendSim Simulation Software Model | | Average |
| .mpd | File List Creator Playlist | | Uncommon |
| .mpd | Microsoft Project Database | | Average |
| .mpj | Minitab Project File | | Average |
| .mpp | Microsoft Project File | | Common |
| .mpt | Microsoft Project Template | | Average |
| .mpx | Microsoft Project Exchange File | | Average |
| .mpz | Miradi Project File | | Average |
| .mq4 | MetaTrader Custom Indicator | | Average |
| .ms10 | Multisim Circuit Design | | Uncommon |
| .mth | Derive Math File | | Average |
| .mtw | Minitab Worksheet File | | Average |
| .mud | Textease Multi User Database | | Average |
| .muf | Alpha Five Licence File | | Uncommon |
| .mw | Maple Worksheet | | Common |
| .mwf | MapGuide Author Map Window File | | Common |
| .mws | Maple Classic Worksheet | | Average |
| .mwx | MicroWorlds EX File | | Uncommon |
| .mxd | ArcGIS Map Document | | Average |
| .myd | MySQL Database Data File | | Average |
| .myi | MySQL MyISAM Index File | | Average |
| .nb | Mathematica Notebook | | Average |
| .nc | Mastercam Numerical Control File | | Common |
| .ndf | SQL Server Secondary Database File | | Average |
| .ndk | Lotus Notes Design Elements File | | Average |
| .ndx | dBASE Index File | | Common |
| .net | netViz Project File | | Average |
| .neta | Netica Binary File | | Average |
| .nfo | Folio Views Infobase File | | Rare |
| .nitf | National Imagery Transmission Format File | | Average |
| .nmind | NovaMind Mind Map File | | Average |
| .not | Notation File | | Common |
| .notebook | SMART Notebook File | | Average |
| .np | Portfolio NetPublish File | | Average |
| .npl | Nokia Playlist File | | Average |
| .npt | Portfolio NetPublish Template | | Average |
| .nrl | Autonomy Interwoven Link File | | Average |
| .ns2 | Lotus Notes 2 Database | | Rare |
| .ns3 | Lotus Notes 3 Database | | Uncommon |
| .ns4 | Lotus Notes 4 Database | | Uncommon |
| .nsf | Lotus Notes Database | | Average |
| .nsf | Lotus Domino Database | | Average |
| .ntx | Clipper Index File | | Uncommon |
| .numbers | Numbers Spreadsheet File | | Common |
| .nvl | UniChem Results File | | Average |
| .nyf | myBase Database File | | Average |
| .oab | Offline Address Book | | Average |
| .obj | Relocatable Object Code | | Average |
| .odb | ABAQUS Database | | Average |
| .odf | Open Document File | | Average |
| .odp | OpenDocument Presentation | | Average |
| .ods | OpenDocument Spreadsheet | | Common |
| .odx | BizTalk Server Orchestration File | | Average |
| .oeaccount | Windows Mail Account File | | Common |
| .ofc | Open Financial Connectivity File | | Average |
| .ofm | OmniForm Form | | Average |
| .oft | Outlook File Template | | Average |
| .ofx | Open Financial Exchange File | | Average |
| .omcs | Office Manager Access File | | Uncommon |
| .omp | Office Manager Document Archive | | Average |
| .ond | Lotus Notes Encapsulated Memo File | | Average |
| .one | OneNote Document | | Average |
| .oo3 | OmniOutliner 3 File | | Average |
| .opf | FlipViewer FlipBook File | | Average |
| .opx | OrgPlus Org Chart | | Average |
| .opx | FlipAlbum Photo Album File | | Average |
| .or2 | Lotus Organizer 2 File | | Rare |
| .or3 | IBM Lotus Organizer 97 File | | Rare |
| .or4 | IBM Lotus Organizer 97 GS File | | Uncommon |
| .or5 | Lotus Organizer 5 File | | Uncommon |
| .or6 | Lotus Organizer 6 File | | Average |
| .org | Lotus Organizer File | | Average |
| .orx | RadiantOne VDS Database Schema | | Uncommon |
| .otf | OpenTuft Tufting Design File | | Average |
| .otl | NoteTab Outline File | | Average |
| .otln | Opal Outline File | | Average |
| .ots | OpenDocument Spreadsheet Template | | Average |
| .out | Output File | | Common |
| .ov2 | TomTom Points of Interest Database | | Common |
| .ova | Octava Musical Score | | Average |
| .ova | Open Virtual Appliance | | Average |
| .ovf | Open Virtualization File | | Common |
| .p96 | Win96 Database File | | Average |
| .p97 | Win97 Database File | | Average |
| .pab | Personal Address Book | | Average |
| .paf | Personal Ancestral File | | Uncommon |
| .pan | Panorama Database File | | Average |
| .pbd | ProBID+ Data File | | Uncommon |
| .pc | Personal Composer File | | Average |
| .pcap | Packet Capture Data | | Average |
| .pcb | Printed Circuit Board Design File | | Average |
| .pcr | PCMark Vantage Benchmark File | | Common |
| .pd4 | Windows Live Photo Gallery Information File | | Average |
| .pd5 | Windows Live Photo Gallery Information File | | Average |
| .pdas | PDAStore Data Store File | | Average |
| .pdb | Program Database | | Very Common |
| .pdb | Palm Desktop Database File | | Common |
| .pdb | Protein Data Bank File | | Average |
| .pdd | Medtronic Programmer Data File | | Average |
| .pdm | PowerDesigner Database File | | Average |
| .pds | Planetary Data System File | | Average |
| .pdx | Product Data eXchange File | | Average |
| .pdx | Adobe Acrobat Index File | | Common |
| .peb | ProEST+ Buildings File | | Uncommon |
| .pec | Brother Embroidery File | | Rare |
| .pep | TurboProject Project File | | Average |
| .pex | Merak Peep Data File | | Average |
| .pf | Windows Prefetcher File | | Uncommon |
| .pfc | AOL Personal File Cabinet | | Common |
| .pfl | Family Lawyer Document | | Average |
| .phb | Motorola Phone Book File | | Average |
| .phm | Pro Home Manager Data File | | Average |
| .pi | Pi Calculation Data File | | Average |
| .pis | PS2DIS Project File | | Uncommon |
| .pjx | FoxPro Project | | Average |
| .pka | Packet Tracer Activity File | | Average |
| .pkb | Oracle Package Body File | | Average |
| .pkh | Oracle Package File | | Average |
| .pks | Oracle Package Spec File | | Average |
| .pkt | Packet Tracer Network Simulation Model | | Average |
| .pln | Spaceman Planogram File | | Uncommon |
| .plw | PicoLog Data File | | Average |
| .pmo | Broderbund Print Meta Object File | | Average |
| .pmr | Performance Monitor Report | | Average |
| .pnproj | Programmer's Notepad Project File | | Average |
| .pnpt | Programmer's Notepad Project Template | | Uncommon |
| .pns | Popnoggin Subject File | | Uncommon |
| .pnt | Popnoggin Theme File | | Uncommon |
| .pod | OpenProj Project File | | Average |
| .poi | Magellan Maestro Point of Interest File | | Average |
| .pos | Trimble Position File | | Rare |
| .postal | TomTom Postal Code File | | Uncommon |
| .pot | PowerPoint Template | | Average |
| .potm | PowerPoint Open XML Macro-Enabled Presentation Template | | Average |
| .potx | PowerPoint Open XML Presentation Template | | Average |
| .pp2 | PingPlotter Data File | | Average |
| .ppf | Publisher Project File | | Average |
| .ppf | Transit NXT Pack Project File | | Average |
| .pps | PowerPoint Slide Show | | Very Common |
| .ppsx | PowerPoint Open XML Slide Show | | Common |
| .ppt | PowerPoint Presentation | | Very Common |
| .pptm | PowerPoint Open XML Macro-Enabled Presentation | | Common |
| .pptx | PowerPoint Open XML Document | | Very Common |
| .prc | Mobipocket eBook File | | Average |
| .pre | Lotus Freelance Graphics File | | Uncommon |
| .prf | Plot Station Plot Request File | | Rare |
| .prj | Project File | | Average |
| .prj | AIMMS Project File | | Average |
| .prm | Route 66 Map File | | Average |
| .prs | Harvard Graphics Presentation | | Average |
| .psa | Photoshop Album Catalog | | Common |
| .psf | SPI Proxy Output File | | Rare |
| .psf | PID Script File | | Rare |
| .psf | GPS Prediction Support File | | Uncommon |
| .psm | Prism Document | | Average |
| .pst | Outlook Personal Information Store File | | Common |
| .ptb | Power Tab File | | Average |
| .ptf | Scrapbook Flair Template | | Average |
| .ptk | Quicken Online Financial Data File | | Average |
| .ptm | MapPoint Map File | | Average |
| .ptn | PaperPort Thumbnail File | | Average |
| .ptt | MapPoint Map Template | | Average |
| .ptz | E-Transcript Bundle File | | Common |
| .pvl | Instalit Library | | Average |
| .pwd | Solid Edge Weldment Document | | Average |
| .pxf | Transit XV Pack Project File | | Average |
| .pxj | RecordNow Project | | Average |
| .pxl | Pocket Excel File | | Average |
| .q07 | QuickTax 2007 Tax Return | | Uncommon |
| .q08 | QuickTax 2008 Tax Return | | Average |
| .q09 | QuickTax 2009 Tax Return | | Average |
| .q3d | Quest3D Project File | | Uncommon |
| .qbw | QuickBooks Data File | | Common |
| .qdat | QuickTime Install Cache File | | Rare |
| .qdf | Snapform File | | Uncommon |
| .qdf | Quicken Data File | | Common |
| .qdfm | Quicken Data File (Macintosh) | | Average |
| .qel | Quicken Electronic Library | | Average |
| .qfx | Quicken Financial Exchange File | | Common |
| .qif | Quicken Interchange Format File | | Average |
| .qpb | Quicken Payroll File | | Average |
| .qpf | Quartus II Project File | | Average |
| .qpf | Quest3D Project | | Uncommon |
| .qph | Quicken Price History File | | Average |
| .qpm | Quick Pallet Maker Input Data | | Average |
| .qpw | Quattro Pro Spreadsheet | | Common |
| .qrp | QuSoft QuickReports File | | Average |
| .qsd | Quicken Data File | | Uncommon |
| .ral | WinRail Track Design File | | Average |
| .rbt | Lego MINDSTORMS NXT Program | | Average |
| .rcd | Arcade File | | Rare |
| .rcg | Recog Character Recognition Set | | Average |
| .rdb | N64 ROM Database | | Average |
| .rdf | Report Definition File | | Average |
| .rdx | Reflex Data File | | Rare |
| .ref | Microsoft Train Simulator Reference File | | Uncommon |
| .ret | BusinessObjects Template | | Average |
| .rf1 | Retirement Forecast File | | Average |
| .rfa | Revit Family File | | Average |
| .rfo | RoboForm File | | Average |
| .rge | Entourage File Archive | | Average |
| .rgn | Garmin Regional Map File | | Average |
| .rgo | RepliGo File | | Average |
| .rmuf | Alpha Five Runtime License File | | Rare |
| .rnq | Renque Model File | | Average |
| .rod | Actuate Report Object Design File | | Average |
| .rog | Roger 2 Input Data File | | Average |
| .roi | Report Object Instance | | Common |
| .roi | Shark Sales System Data File | | Average |
| .rou | Gerber Route File | | Average |
| .rpp | REAPER Project File | | Average |
| .rpt | Crystal Reports File | | Average |
| .rrt | Rhapzode Resource Template | | Uncommon |
| .rsc | Symbian Application Compiled Resource File | | Average |
| .rsd | RealSQLDatabase File | | Average |
| .rsw | R&R SQL Report Writer Report File | | Average |
| .rte | Navigation Route | | Average |
| .rte | Revit Project Template | | Average |
| .rvt | Revit Project File | | Common |
| .rwg | Random Word Generator Project File | | Rare |
| .rzb | Red Zion Book File | | Average |
| .s85 | Sabre Airline Solutions Chart | | Average |
| .saf | Street Atlas USA Map File | | Common |
| .sam07 | SAM 2007 Package | | Rare |
| .sar | Sibelius Arrange Style | | Average |
| .sav | SPSS Data File | | Average |
| .sbd | Superbase Data Definition File | | Uncommon |
| .sbf | SmartBroker Data | | Average |
| .sbf | Superbase Database File | | Uncommon |
| .sbq | Superbase QuickReports File | | Uncommon |
| .sbt | Superbase Data Notes File | | Rare |
| .sca | Norton AntiVirus Scan File | | Average |
| .scf | DNA Sequence Chromatogram File | | Average |
| .sch | EAGLE Schematics File | | Average |
| .sdb | OpenOffice.org Base Database File | | Very Common |
| .sdb | ServerBoss Database File | | Average |
| .sdb | MonKey Office SQLite Database File | | Average |
| .sdc | OpenOffice.org Calc Spreadsheet | | Common |
| .sdf | Standard Data File | | Very Common |
| .sdf | SQL Server Compact Database File | | Average |
| .sdf | Spatial Data Format File | | Common |
| .sdp | Session Description Protocol File | | Average |
| .sdq | SAS Data File | | Average |
| .sds | OpenOffice.org Chart | | Average |
| .sds | SDS Apps Data File | | Uncommon |
| .sen | SenTest Data File | | Average |
| .seo | SEO Note File | | Average |
| .seq | DNA Sequence Text File | | Average |
| .ser | GeneMapper Project File | | Uncommon |
| .sgml | Standard Generalized Markup Language File | | Average |
| .sgn | Slax Boot File | | Uncommon |
| .shp | ESRI Shapefile | | Average |
| .shs | Microsoft Scrap File | | Rare |
| .shx | Shapefile Index File | | Average |
| .skc | SideKick Card File | | Rare |
| .skv | Semicolon Separated Values File | | Average |
| .skv | XLANG Schedule Drawing File | | Average |
| .skx | XLANG Schedule File | | Average |
| .sle | Sisulizer Package File | | Average |
| .slk | Symbolic Link File | | Uncommon |
| .slp | Sisulizer Project File | | Average |
| .snapfireshow | Corel SnapfireShow File | | Average |
| .sonic | DigitalMedia Project File | | Rare |
| .soundpack | SoundPackager Sound Package | | Uncommon |
| .spo | SPSS Statistical Data Output File | | Uncommon |
| .sps | SPSS Program File | | Average |
| .spub | Disc Cover File | | Average |
| .spv | SPSS Output File | | Average |
| .sq | Sysquake Program | | Average |
| .sqd | SQ Data File | | Average |
| .sql | Structured Query Language Data | | Very Common |
| .sqlite | SQLite Database File | | Average |
| .sqr | SQL Program File | | Average |
| .sta | ABAQUS Status File | | Average |
| .stc | StarOffice Calc Spreadsheet Template | | Average |
| .stf | Exchange 2000 Server Temporary File | | Uncommon |
| .stk | Stickfigure Animator File | | Average |
| .stl | Fireworks Style Library | | Uncommon |
| .stm | Exchange Streaming Media File | | Common |
| .stp | Analysis Studio Project Information File | | Average |
| .str | dBASE Structure List Object File | | Average |
| .stt | Streets & Trips Map Template | | Average |
| .stw | STATISTICA Workbook | | Average |
| .styk | Stykz Stick Figure | | Average |
| .stykz | Stykz Animation | | Average |
| .swk | StudyWorks Save File | | Average |
| .sxc | StarOffice Calc Spreadsheet | | Average |
| .sxi | StarOffice Impress Presentation | | Average |
| .sy3 | Harvard Graphics Symbol File | | Rare |
| .t01 | TaxCut 2001 File | | Average |
| .t02 | TaxCut 2002 File | | Average |
| .t03 | TaxCut 2003 File | | Average |
| .t04 | TaxCut 2004 File | | Average |
| .t05 | TaxCut 2005 Tax Return | | Average |
| .t06 | TaxCut 2006 Tax Return | | Average |
| .t07 | TaxCut 2007 Tax Return | | Average |
| .t08 | TaxCut 2008 Tax Return | | Common |
| .t09 | At Home 2009 Tax Return | | Common |
| .t2 | Textease 2000 File | | Uncommon |
| .t3001 | TARGET 3001! Circuit Design Project File | | Average |
| .tax2008 | TurboTax 2008 Tax Return | | Average |
| .tax2009 | TurboTax 2009 Tax Return | | Common |
| .tb | Tabbery Tab File | | Average |
| .tbk | ToolBook File | | Average |
| .tbl | StarCraft Information Table | | Average |
| .tcc | TimeCalc Classic Data File | | Average |
| .tcx | Training Center Database File | | Average |
| .tda | Palm To-Do File | | Average |
| .tda | Java Application Thread Dump | | Average |
| .tdl | Tab Delineated Format File | | Uncommon |
| .tdm | LabVIEW Binary Measurement File | | Average |
| .tdt | FirstBreak Concrete Test File | | Uncommon |
| .tdt | THOR Data Tree File | | Average |
| .te | Textease CT Database File | | Common |
| .te3 | WinTrack Object File | | Average |
| .teacher | Senteo Teacher Database File | | Uncommon |
| .tef | TablEdit Tablature | | Average |
| .tet | Textease CT Template | | Average |
| .tfa | TreeSoft CashFlow Analysis Data File | | Average |
| .tfd | Tape Format Requirements Document | | Average |
| .tfrd | Tape Image Format Requirements Document | | Average |
| .tjp | TaskJuggler Project File | | Average |
| .tk3 | TK3 Multimedia eBook | | Average |
| .tkfl | TKLinks Saver Favorite Links File | | Average |
| .tmw | Translation Memory Data File | | Uncommon |
| .tol | AOL Tool File | | Rare |
| .topc | TopicCrunch Project File | | Average |
| .tpb | GROMACS Binary Input File | | Average |
| .tpf | Transit NXT Pack Translation File | | Average |
| .tps | Multi Channel Measurement File | | Average |
| .tr3 | TomeRaider eBook File | | Average |
| .tra | WinTrack Railroad Track File | | Average |
| .trd | TrID Definitions Package | | Average |
| .trk | Garmin Track File | | Rare |
| .trk | CompeGPS Land Track File | | Average |
| .trs | Rosetta Stone Language Data | | Common |
| .trs | WinTrack Railroad Track Text File | | Average |
| .trx | Firmware Image File | | Uncommon |
| .trx | WebAuthorize Batch File | | Uncommon |
| .tst | TestPoint Test File | | Average |
| .tsv | Tab Separated Values File | | Common |
| .ttk | Catalyst Translation Toolkit | | Average |
| .txa | Midas ViewPoint Text Array List | | Average |
| .txd | Game Texture Dictionary | | Average |
| .txf | Tax Exchange Format | | Average |
| .txf | Transit XV Pack Translation File | | Uncommon |
| .uccapilog | Microsoft UCC API Log File | | Common |
| .ud | OmniPage User Dictionary | | Uncommon |
| .udb | Dynamics AX User Database File | | Average |
| .udeb | Debian Package File | | Uncommon |
| .uds | Uniform Data System File | | Uncommon |
| .uds | Sierra Generations File | | Rare |
| .ulf | Universal List File | | Average |
| .ulz | USBlyzer Data Capture File | | Average |
| .update | ISAPI Update File | | Uncommon |
| .upoi | iGO Points of Interest File | | Average |
| .usr | FileMaker Pro Database File | | Average |
| .uvf | Uncertain Value Format | | Average |
| .uwl | User Word List File | | Common |
| .val | Values List | | Average |
| .val | Valodas Dictionary File | | Uncommon |
| .vbpf1 | Virtual Business - Personal Finance Data File | | Average |
| .vcd | Value Change Dump File | | Average |
| .vce | Visual CertExam Exam File | | Average |
| .vcf | vCard File | | Very Common |
| .vcs | vCalendar Event File | | Average |
| .vdb | Symantec Virus Database File | | Common |
| .vdx | Visio Drawing XML File | | Average |
| .vfs | VentaFax Schedule File | | Rare |
| .vi | LabVIEW Virtual Instrument File | | Average |
| .vip | Stitch Pattern File | | Uncommon |
| .vle | Virtual Labs Electricity Circuit File | | Rare |
| .vlg | VentaFax Logbook File | | Rare |
| .vmt | Valve Material File | | Average |
| .voi | VOI Group File | | Average |
| .vok | PocketVok Vocabulary File | | Average |
| .vrd | Visio Report Definition File | | Average |
| .vscontent | Visual Studio Content File | | Average |
| .vsx | Visio Stencil XML File | | Average |
| .vtx | Visio Template XML File | | Average |
| .vxml | VoiceXML File | | Common |
| .w02 | Split Archive File | | Rare |
| .wab | Windows Address Book | | Common |
| .wb1 | Corel Quattro Pro File | | Uncommon |
| .wb2 | Corel Quattro Pro File | | Average |
| .wb3 | Corel Quattro Pro 7 and 8 File | | Common |
| .wdb | Microsoft Works Database | | Average |
| .wdq | Offline Explorer Queue File | | Uncommon |
| .wea | Ecotect Weather File | | Average |
| .wfd | Wayfinder Map File | | Rare |
| .wfm | dBASE Form | | Uncommon |
| .wgp | Web Gallery Project | | Average |
| .wgt | XNBC Synaptic Weights File | | Average |
| .wgt | IMPS Data File | | Average |
| .windowslivecontact | Windows Live Contacts File | | Common |
| .wjr | ReGet Deluxe Data File | | Average |
| .wk1 | Lotus Worksheet | | Uncommon |
| .wk2 | Lotus 2 Worksheet | | Rare |
| .wk3 | Lotus 3 Worksheet | | Uncommon |
| .wk4 | Lotus 4 Worksheet | | Uncommon |
| .wk5 | Lotus 5 Worksheet | | Uncommon |
| .wke | Lotus 1-2-3 Educational Version Worksheet | | Rare |
| .wki | Lotus 2 Worksheet | | Average |
| .wks | Works Spreadsheet | | Very Common |
| .wks | Lotus 1-2-3 Spreadsheet | | Uncommon |
| .wku | Lotus 1-2-3 Spreadsheet | | Average |
| .wlmp | Windows Live Movie Maker Project File | | Common |
| .wmdb | Windows Media Database File | | Average |
| .wor | MapInfo Workspace File | | Average |
| .wpc | Pazzles Cutting File | | Uncommon |
| .wpc | WordPad Converter File | | Average |
| .wpf | WordPerfect Form | | Average |
| .wpo | HOLUX Waypoint File | | Uncommon |
| .wpo | Technopress Waypoint 2D File | | Rare |
| .wq1 | Quattro Pro for DOS Spreadsheet File | | Rare |
| .wq2 | Quattro Pro for DOS Spreadsheet File | | Rare |
| .wtb | Win-Test Binary Log File | | Average |
| .wtr | Encarta File | | Rare |
| .xbk | SMART Notebook File | | Uncommon |
| .xdb | PowerDesigner Database Definition File | | Average |
| .xdb | Symantec Virus Database File | | Common |
| .xdp | XML Data Package | | Average |
| .xds | LcdStudio Design File | | Uncommon |
| .xef | eManager Form Data | | Average |
| .xem | PowerDesigner Model definition File | | Average |
| .xfd | XFD File | | Uncommon |
| .xfo | XSL-FO Formatted Form | | Average |
| .xft | Adobe Form Designer 5.0 File | | Average |
| .xl | Excel Spreadsheet | | Uncommon |
| .xlc | Excel Chart | | Average |
| .xlgc | ExpressK Database File | | Uncommon |
| .xlr | Works Spreadsheet | | Common |
| .xls | Excel Spreadsheet | | Very Common |
| .xlsb | Excel Binary Spreadsheet | | Average |
| .xlsm | Excel Open XML Macro-Enabled Spreadsheet | | Average |
| .xlsx | Microsoft Excel Open XML Document | | Very Common |
| .xlt | Excel Template | | Average |
| .xltm | Excel Open XML Macro-Enabled Spreadsheet Template | | Common |
| .xltx | Excel Open XML Spreadsheet Template | | Common |
| .xlw | Excel Workbook | | Average |
| .xmcd | Mathcad Worksheet File | | Average |
| .xml | XML File | | Very Common |
| .xmlper | LeCroy Binary Waveform File | | Average |
| .xmpz | Miradi XML Project File | | Rare |
| .xpg | Autoplay Media Studio Exported Page | | Average |
| .xpj | Micro Planner X-Pert Project File | | Average |
| .xpm | Micro Planner Manager File | | Average |
| .xpt | SAS Transport File | | Average |
| .xrp | RationalPlan Project File | | Average |
| .xsl | XML Style Sheet | | Common |
| .xslt | XSL Transformation | | Average |
| .xsn | InfoPath Form Template File | | Uncommon |
| .xtm | Xtremsplit Data File | | Average |
| .xtm | CmapTools Exported Topic Map | | Uncommon |
| .xtp | XTree Data File | | Rare |
| .xxd | Brixx Planner Calendar | | Rare |
| .yam | Yahoo! Auctions Data | | Average |
| .zap | Zone Alarm Pro Data File | | Average |
| .zdb | Quicken Online File | | Average |
| .zdb | EPSQ Database | | Average |
| .zdc | CD Catalog Expert Database File | | Average |
| .zix | Quicken Online File | | Average |
| .zmc | ZoneAlarm Quarantine File | | Average |
| .zpl | Zoom Player Play List | | Average |
| .^^^ | Pervasive.SQL Database File | | Uncommon |
| .{pb | Corel WordPerfect Document Index File | | Rare |
| .~hm | HostMonitor TestList Backup File | | Uncommon |
