Search for data file formats and extensions that begin with the letter O, or search more than 4,000 file extensions by the letter or number the file format starts with.
With literally thousands of data file formats employed by Windows and Window-based apps, keeping track of all the file extensions employed by your software applications and programs can be quite a challenge. Fortunately, Webopedia’s Complete List of Data File Formats and File Extensions makes it quick and easy to sift through thousands of file extensions and data file formats to find exactly what you need. You can peruse the full list or search for data formats and file extensions based on the letter they start with from the table below.
Data File Formats that Begin with the Letter ‘O’
|
| .o |
Object file (unix – Atari – GCC) |
| .o$$ |
Outfile (Sprint) |
| .oaz |
Fax (NetFax Manager) |
| .ob |
Object cut/paste file (IBM LinkWay) |
| .obd |
MS Office Binder |
| .obj |
Object code (Intel Recolatable Object Module) |
| .obr |
Object browser data file (Borland C++) |
| .obs |
Script (ObjectScript) |
| .obv |
Visual interface (ObjectScript) |
| .oca |
Control Typelib Cache |
| .ocf |
Object Craft File (Object Craft) |
| .ocm |
AOL Advertising Control files |
|
Internet Odyssey 2 Update |
| .ocp |
Advanced Art Studio |
|
Offline Commander Project file |
| .ocr |
Incoming fax transcribed to text (FAXGrapper) |
| .oct |
Radiance Octree Format |
| .ocx |
OLE ActiveX custom control |
| .odf |
Open Document Interchange |
|
BattleZone Cartographers Guild file |
|
Star Trek Armada Ship/Structure Infomation |
| .odg |
OpenDocument Graphic file |
| .odl |
Type library source (Visual C++) |
| .odp |
OpenOffice Presentation file |
| .ods |
OpenOffice Spreadsheet file |
| .odt |
OpenOffice OpenDocument text document |
| .oeb |
Outlook Express Backup Wizard |
| .oem |
TextSetup OEM file |
| .ofc |
Open Financial Connectivity file |
| .ofd |
Form definition (ObjectView) |
| .off |
Object File Format vector graphics |
| .ofm |
Adobe font |
| .oft |
MS Outlook Item Template |
| .ofx |
Olicom Fax |
|
Open Financial Exchange file |
| .ogg |
Ogg Vorbis Codec Compressed WAV file |
| .ogm |
Ogg Vorbis Compressed Video file |
| .ogv |
Video Container file |
| .okt |
Music (Oktalizer) |
| .olb |
Object library (VAX) |
| .old |
Backup file |
| .ole |
Object Linking and Embedding Object |
| .oli |
Text file (Olivetti) |
| .oma |
OpenMG Music file |
| .omf |
Open Media file |
| .omg |
OpenMG Jukebox |
| .oms |
Briggs Softworks Order Maven |
|
Macintosh MP3 Music Format |
|
Omega Downloader Configuration file |
| .ond |
Lotus Notes-related file |
| .one |
OneNote Document File |
| .ont |
Bible file |
| .oom |
Swap file (Shroom) |
| .opd |
Omnipage file |
| .opf |
Flip Album file |
|
Open Packaging Format file |
| .opl |
Psion Organiser Programming Language Source file |
| .opn |
Active options (Exact) |
| .ops |
Microsoft Office profile settings file |
| .opt |
Optimize support file (QEMM) |
| .opw |
Organization chart (Org Plus for Windows) |
| .opx |
Inactive options (Exact) |
| .or2 |
Lotus Organizer 2 file |
| .or3 |
Lotus Organizer 97 file |
| .or4 |
Lotus Organizer file |
| .or5 |
Lotus Organizer file |
| .ora |
Parameter file (Oracle) |
| .org |
Calendar file (Lotus Organizer) |
| .osd |
Open Software Description file |
| .oss |
MS Office Saved Search |
| .ost |
Microsoft Outlook Offline file |
| .otf |
Open Type Format |
| .otl |
Outline font description (Z-Soft Type Foundry) |
| .otx |
Text file (Olivetti Olitext Plus) |
| .out |
Output file |
| .ov1 |
Overlay file (part of program to be loaded when needed) |
| .ov2 |
Overlay file (part of program to be loaded when needed) |
| .ovd |
Datafile (ObjectVision) |
| .ovl |
Overlay file (part of program to be loaded when needed) |
| .ovr |
Overlay file (part of program to be loaded when needed) |
| .ovw |
Cool Edit Pro Overviewfile |
|
Cubase .WAV File Image |
|
DIANA Overview file |
| .ows |
Web Studio 2 Project file |
| .oxt |
Open Office Extension file |
Recommended Reading: An Introduction to Data File Formats and Their File Extensions
This article was last updated on April 12, 2012
