file extension Windows/OS2/Apple/Unix/Dos

File ExtensionsWindows/OS2/Apple/UNIX

Select Extension by starting letter:

A - B - C - D - E - F - G - H - I - J - K - L - M -
N - O - P - Q - R - S - T - U - V - W - X - Y - Z -
OTHER - Allowedchars in file names - what is an extension?
Links Converter
graphical file formats - Potentially harmful extensions contributors

internals

Bookmark this site

Search: Use ctrl-F to search foritem

Universal dump utility for non-destructive dump/list/string search etc dump.zip

O = Mime: application/octet-stream
O = Object file (Unix/GCC)
O$$ = Sprint outfile
O00 = o00_auto_file special configuration file for application(binary format)
O01 = Typhoon Voice File
O2C = AMglossar images file
O7$3 = (MAC FILE_TYPE) Omnis
O8O = Mediator5 Repositorytabs Vorlagen.006 file
OA2 = Mime: application/vnd.fujitsu.oasys2
OA3 = Mime: application/vnd.fujitsu.oasys3
OAB = MS Outlook Address Book
OAS = Japanese : Word processor document (Fujitsu OAS)
OAS = Mime: application/vnd.fujitsu.oasys
OAZ = fax: NetFax Manager
OAZ = OAZ Fax image format
OB = IBM LinkWay Object cut/paste file
OB$ = Microsoft compressed OBJ decompress with UNPACK.EXE
OBD = Microsoft Office binder template
OBD = Mime: application/x-msbinder
OBE = System Dll Oobe file
OBJ = Intel Relocatable OBJect Module = compiler/assembler output
OBJ = Objects : Metatools' Bryce Support file
OBJ = Wavefront 3D Object
OBJ_ = (MAC FILE_TYPE) Object File
OBK = OrCAD Capture Design/Library
OBR = Borland C++ object browser data
OBS = Script (ObjectScript)
OBT = MS Office Binder Template
OBV = ObjectScript visual interface
OBY = EPOC : ROM image
OBZ = Microsoft Office Binder Wizard
OC_ = Game: doko inst file
OCA = OLE Custom Control Library Information
OCA = Visual Basic control typelib cache
OCDC = (MAC FILE_TYPE) Mathematica Document
OCF = Object Craft File
OCM = Netscape Communicator Aim file
OCP = Advanced Art Studio image format
OCR = Incoming fax transcribed to text / FAXGrapper
OCT = Musical file (Octalizer)
OCX = OLE Custom Control, 32 bit (Visual Basic or C++) ActiveX control
OD1 = Omnis5 Database File
OD2 = Omnis5 Database File
OD3 = Omnis5 Database File
OD4-9 = Omnis5 Database File
OD_ = Oracle driver, .DLL compressed
ODA = Mime: application/oda
ODA = ODA document
ODA = Raster image (CALS Group IV Type 2)
ODA = Used with OCX
ODB = ArcView : Object Database ASCII file (ODB format)
ODC = odcfile special configuration file for application(binary format) Content Type text/x-ms-odc
ODC = odcfile special configuration file for application(binary format) PerceivedType text PerceivedType text Content Type text/x-ms-odc
ODCCUBEFILE = odccubefile special configuration file for application(binary format)
ODCCUBEFILE = odccubefile special configuration file for application(binary format) NoOpen Content Type text/x-ms-odc
ODCCUBEFILE = odccubefile special configuration file for application(binary format) NoOpen PerceivedType text Content Type text/x-ms-odc
ODCDATABASEFILE = odcdatabasefile special configuration file for application(binary format)
ODCDATABASEFILE = odcdatabasefile special configuration file for application(binary format) NoOpen Content Type text/x-ms-odc
ODCDATABASEFILE = odcdatabasefile special configuration file for application(binary format) NoOpen PerceivedType text Content Type text/x-ms-odc
ODCNEWFILE = odcnewfile special configuration file for application(binary format)
ODCNEWFILE = odcnewfile special configuration file for application(binary format) NoOpen Content Type text/x-ms-odc
ODCNEWFILE = odcnewfile special configuration file for application(binary format) NoOpen PerceivedType text Content Type text/x-ms-odc
ODCTABLEFILE = odctablefile special configuration file for application(binary format)
ODCTABLEFILE = odctablefile special configuration file for application(binary format) NoOpen Content Type text/x-ms-odc
ODCTABLEFILE = odctablefile special configuration file for application(binary format) NoOpen PerceivedType text Content Type text/x-ms-odc
ODE = Microsoft Office file
ODF = Open Document Interchange Format (ODIF)
ODH = Object Definition Head
ODIF = Open Document Interchange Format
ODL = Object Definition Language (Object Library Source for OLE applications)
ODP = PowerPoint.OpenDocumentPresentation.12 open with: "%ProgramFiles%\Microsoft Office\Office12\POWERPNT.EXE" "%1" PerceivedType document PerceivedType document Content Type application/vnd.oasis.opendocument.presentation
ODS = NCompass Labs (Internet script/tbv)
ODT = odtfile open with: "%ProgramFiles%\Windows NT\Accessories\WORDPAD.EXE" "%1" PerceivedType document PerceivedType document
ODT = Word.OpenDocumentText.12 open with: "%ProgramFiles%\Microsoft Office\Office12\WINWORD.EXE" /n /dde PerceivedType document PerceivedType document Content Type application/vnd.oasis.opendocument.text
ODVI = (MAC FILE_TYPE) LaTeX Filea Documentactex
OECl = (MAC FILE_TYPE) Microsoft Database Cach
OEDB = (MAC FILE_TYPE) Microsoft Email Databas
OEM = Sb_awe keys Sb_nt file
OF = Audio Utility Tuningwrench compressed file
OFC = Open Financial Connectivity File
OFD = ObjectView Form Definition
OFF = 3D Object File Format
OFM = PostScript font description file
OFN = MS Office File New (Other Office Documents)
OFS = Outlook.File.ofs special configuration file for application(binary format)
OFT = Microsoft Outlook template
OFX = Olicom Fax image format
OGA = special configuration file for application(binary format) Source Filter {31CA0186-1FF0-4181-AA38-3CA4040BD260} PerceivedType text
OGC = Organica doc
OGG = Ogg Vorbis audio file open-source music encoder http://www.xiph.org/ogg/vorbis
OGG = Saltlake city game file
OGL = Overlay source code
ogle = (MAC FILE_TYPE) Picture Viewer
OGM = video format
OGS = Origin File
OGX = exported classes and resources, Microsoft C++ Component Gallery
OHP = Dos7 file
OHS = Outbound History (Bink/+)
OID = Object Interaction Diagram (Prosa/OM)
OIF = QuickBase Web-sharable Database Interchange File
OIL = Open Image Library Format image format
OK = QEDIT file
OKR = "3-D Fassade Plus" Feldeinteilung module file
OKT = Oktalyzer music module (MOD) file
OL_ = green_line file
OLB = AUTOGEN file
OLB = MS Project Object Library
OLB = Object library VAX
oLB2 = (MAC FILE_TYPE) CanOpener Library
OLD = Backup file
OLE = Object Linking and Embedding (generic name)
OlG1 = (MAC FILE_TYPE) Lynx
OLI = Olivetti text file
OLK = MS Mail mailbag lock
OLN = MS Visual C++ Outline examples
OLS = OfficeListShortcut open with: "%ProgramFiles%\Microsoft Office\Office12\MSPUB.EXE" %1 NoOpen PerceivedType text Content Type application/vnd.ms-publisher
OLT = MS Visual C++ Outline examples
OLTB = (MAC FILE_TYPE) OLE Types
OMA = VLC.oma special configuration file for application(binary format)
OMC = Mime: application/x-omc
OMCD = Mime: application/x-omcdatamaker
OMCR = Mime: application/x-omcregerator
OMD = Class model (Prosa/OM)
OMEG = (MAC CREATOR CODE) Mathematica
OMEG = (MAC CREATOR CODE) Mathematica (all kinds of files)
OMEG = (MAC FILE_TYPE) Mathematica
OMF = Avid video editor interchange data
ON = Audio Utility Tuningwrench compressed file
OND = Lotus Notes file
ONE = Pathtrace licensing key file, holds licensing data for programming the (typically dongle based) EdgeCAM application licensing.
ONEPKG = OneNote.Package open with: "%ProgramFiles%\Microsoft Office\Office12\ONENOTE.EXE" "%1" NoOpen PerceivedType text Content Type application/msonenote
ONEPKG = OneNote.Package open with: "%ProgramFiles%\Microsoft Office\Office12\ONENOTE.EXE" "%1" PerceivedType document PerceivedType document Content Type application/msonenote
ONETOC = OneNote.TableOfContents open with: "%ProgramFiles%\Microsoft Office\Office12\ONENOTE.EXE" /navigate "%1"
ONETOC2 = OneNote.TableOfContents.12 open with: "%ProgramFiles%\Microsoft Office\Office12\ONENOTE.EXE" /navigate "%1"
ONG = Onglet
ONLN = (MAC FILE_TYPE) Apple DocViewer File
ONPF = (MAC FILE_TYPE) Apple DocViewer Prefs
ONX = Onyx Graphics Postershop File
OO1 = Typhoon : Voice file
OOGL = 3d Graphic
OOM = Shroom swap
OP = Rescue Disk file
OP2 = Musplay 1.72 file
OP_ = GKSetup support file
OPA = Psion OPL object file
OPC = Microsoft Office 97 upgrade wizard clean-up
OPENGL = OpenGL Web site
OPENTAG = OpenTag
OPJ = OrCAD Capture Project
OPL = Psion OPL language source code
OPN = Active options (Exact)
OPO = Psion OPL object
OPS = ???
OPT = Delphi Project Options (text, current project settings)
OPT = digital line graph optional vector data (surface/terrain)
OPT = Microsoft Developer Studio workspace options
OPT = options, Configuration information used by several programs
OPT = QEMM Optimize support
OPW = Org Plus for Windows organization chart
OPX = Banner Blue Org Chart
OPX = Exact inactive options
OPX = Microsoft Office Organization Chart
OPX = OrgPlus organization chart softw. http://www.orgplus.com
OPX = Psion Organizer Programming Language
OQY = MS Excel OLAP Query File
OR2 = Lotus Organizer 2
OR2 = Mime: application/vnd.lotus-organizer
OR3 = Lotus Organizer 97
OR3 = Mime: application/vnd.lotus-organizer
OR8 = Rational Rose Oracle8 database model report
ORA = Oracle parameter
ORC = Oracle 7 Script
ORC = CSOUND orchestra project files
ORC = MIDI File
ORD = Bc45 Owl file
ORDEREDTEST = VisualStudio.orderedtest.9.0 open with: "%ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE\devenv.exe" /dde Content Type application/xml
ORDEREDTEST = VisualStudio.orderedtest.9.0 open with: "%ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE\devenv.exe" /dde NoOpen PerceivedType text Content Type application/xml
ORF = Photoshop.CameraRawFileOlympus.10 open with: "%ProgramFiles%\Adobe\Adobe Photoshop CS3\Photoshop.exe" "%1" PerceivedType Image PerceivedType Image Content Type application/xml
ORG = Lotus organiser file
ORG = Lotus Organizer calendar
ORG = Microcal Origin plot
ORG = Mime: application/vnd.lotus-organizer
ORG2+ = Lotus organiser file
ORI = Original
ORIG = Gen original file
ORIGINAL = Netobjects fusion Components Bbscomp message file
ORQ = Mime: application/ocsp-request
ORS = Mime: application/ocsp-response
OS2 = os2 system file
OS3 = Os2warp3 file
osas = (MAC FILE_TYPE) AppleScriptibrarytanlscpt
osax = (MAC FILE_TYPE) Scripting Additionanlosax
OSC = Formula one 2001 Options file
OSC = Fruitypro Samples Ss_effects file
OSD = driver file
OSDX = opensearchdescription open with: %SystemRoot%\explorer.exe PerceivedType document PerceivedType document Content Type application/opensearchdescription+xml
OSF = Dist Bin file
OSP = CWCDATA file
OSS = Microsoft Office Search
OSS = Recorded sound from /dev/dsp and Sun /dev/audio
OST = Microsoft Outlook/Inbox offline folder
OTA = Mime: image/x-ota-bitmap
otan = (MAC FILE_TYPE) Open Transport
OTF = otffile, open with: fontview.exe
otgl = (MAC FILE_TYPE) Open Transport Prefs File
OTH = ".OtherFolder", MS Power Toys Explorer tool
OTL = OpenTrap Event Log
OTL = Super NoteTab template file
OTL = Ventura Publisher's Type Foundry Outline Editor format
OTL = Z-Soft Type Foundry outline font description
OTLB = (MAC FILE_TYPE) Microsoft OLE Type File
OTM = OTMFile special configuration file for application(binary format)
otnc = (MAC FILE_TYPE) Open Transport Prefs File
OTP = Origin File(of originlab)
otsl = (MAC FILE_TYPE) Open Transport Library
OTX = Olivetti Olitext Plus text
OUT = Extract individual sound files from the input file(sox)
OUT = OUTput
OUTLOOK97 = Outlook97 mail format for custom mail
OV0 = Objective Voice E-mail for windows
OV1 = Overlay file (part of program to be loaded when needed)
OV2 = Overlay file (part of program to be loaded when needed)
OV3 = Overlay file (part of program to be loaded when needed)
OVD = ObjectVision data
OVE = Cakewalk Overture Score
OVF = Object Vision
OVG = ObjectVision converted graphic file
OVL = OVerLay (part of program to be loaded when needed), program code for DOS
OVM = Bhv Tonstudio Platin file
OVR = OVeRlay (part of program to be loaded when needed), program code for DOS
OWL = Bc45 Owl file
OWS = Oxford dictionary (oxford university press)
OXR = Virus Safe Web Driver
OXT = audio mod OXX
OYZ = Lotus Approach alternate dBASE index
OZM = Sharp Organizer memo bank
OZP = Sharp Organizer telephone bank

Search: Use ctrl-F to search for item

Universal dump-utility for non-destructive dump/list/search string etc dump.zip

Select Extension by starting letter:

A- B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U -

V- W - X - Y - Z - OTHER - Allowed chars in Filenames - what is an extension?

 

If you find an extension missing, write! No guarantee given for completeness or correctness. If you feel an extension is outdated, write!
Authors and retailers: it is in the interest of us all and our customers to avoid the double use of extensions! Please help us keep this compilation up todate!
Send extension data to: update@file-ext.4uj.org
Any questions for not listed extensions or "what program opens xxx": search@file-ext.4uj.org
Any other questions, remarks, praise, flaming or reproach: info@file-ext.4uj.org
Compilation Copyright (c) 2002 R.Bitsch, Compilation Copyright (c) 2009,2010 R.Cooper-Bitsch