| .EPD | Interscape | Tietokantatiedostot | ChessDB Extended Position Description | ChessDB | Interscape |
| .ERD | Open Source | Tietokantatiedostot | Entity Relation Diagram | DBeaver | Open Source |
| .ESL | Microsoft Corporation | Tietokantatiedostot | Visual FoxPro Distributable Support Library | Microsoft Visual FoxPro | Microsoft Corporation |
| .FBM | Michael Loren "Fuzzy" Mauldin | Tietokantatiedostot | Fuzzy Bitmap Image | Graphics Converter Pro | Newera Software Technology, Inc. |
| .FCD | Smart Projects | Tietokantatiedostot | Virtual CD Format | IsoBuster | Smart Projects |
| .FDB | Extensis | Tietokantatiedostot | Portfolio Catalog | Portfolio | Extensis |
| .FF3 | Creative Companion Europe | Tietokantatiedostot | FreeForm Database File | FreeForm 4.1 | Creative Companion Europe |
| .FGR | Fourth Ray Software | Tietokantatiedostot | FRSGiftRegistry Database File | FRSGiftRegistry | Fourth Ray Software |
| .FIC | PC SOFT | Tietokantatiedostot | WinDev Hyper File Database | WinDev | PC SOFT |
| .FIV | Forensic Innovations | Tietokantatiedostot | File Investigator Database | File Investigator | Forensic Innovations |
| .FM3 | IBM | Tietokantatiedostot | Lotus 1-2-3 Spreadsheet Format File | Microsoft Excel | Microsoft Corporation |
| .FM5 | FileMaker Inc. | Tietokantatiedostot | FileMaker 5 Database | FileMaker Pro | FileMaker Inc. |
| .FMP | Dreamingsoft | Tietokantatiedostot | 123 Flash Menu Project | 123 Flash Menu | Dreamingsoft |
| .FOC | Information Builders | Tietokantatiedostot | FOCUS Database | FOCUS for Unix | Information Builders |
| .FOL | SoftKey | Tietokantatiedostot | PFS First Choice Database File | SoftKey PFS First Choice | SoftKey |
| .FP3 | Fast Report | Tietokantatiedostot | FastReport Prepared Report File | Fast Report Viewer | Fast Report |
| .FP5 | FileMaker Inc. | Tietokantatiedostot | FileMaker Pro 5 Database | FileMaker Pro | FileMaker Inc. |
| .FP7 | FileMaker Inc. | Tietokantatiedostot | FileMaker Pro Database File | FileMaker Pro | FileMaker Inc. |
| .FPT | Sage | Tietokantatiedostot | ACT! Data File | Act! | Swiftpage, Inc. |
| .FRM | Oracle Corporation | Tietokantatiedostot | MySQL Database Format File | MySQL | Oracle Corporation |
| .FW | Selections & Functions | Tietokantatiedostot | Framework Database | Framework | Selections & Functions |
| .FW2 | Selections & Functions | Tietokantatiedostot | Framework Database | Framework | Selections & Functions |
| .FW3 | Selections & Functions | Tietokantatiedostot | FrameWork III Database | Framework | Selections & Functions |
| .GDB | Garmin | Tietokantatiedostot | GPS Database File | Garmin BaseCamp | Garmin |
| .GJD | Trilobyte | Tietokantatiedostot | The 7th Guest Media File | The 7th Guest | Trilobyte |
| .GPK | Steinberg | Tietokantatiedostot | WaveLab Audio Peak File | WaveLab | Steinberg |
| .GRX | Headlight Software | Tietokantatiedostot | Getright Exported List | GetRight | Headlight Software |
| .GWI | Novell, Inc. | Tietokantatiedostot | GroupWise Database Shortcut File | GroupWise | Novell, Inc. |
| .H! | Perfect world Inc. | Tietokantatiedostot | Perfect Database Help Database File | Unknown Software | Unknown Developer |
| .HDB | HansaWorld | Tietokantatiedostot | HansaWorld Database File | HansaWorld Enterprise | HansaWorld |
| .HI2 | PHD Computer Consultants | Tietokantatiedostot | Spy-CD CD Search Database File | Spy-CD | PHD Computer Consultants |
| .HIS | Interscape | Tietokantatiedostot | FindinSite Database Definition File | PHDCC FindinSite-CD | Interscape |
| .HIW | PHD Computer Consultants | Tietokantatiedostot | Spy-CD CD Search Database File | Spy-CD | PHD Computer Consultants |
| .HIZ | PHD Computer Consultants | Tietokantatiedostot | Spy-CD CD Search Database File | Spy-CD | PHD Computer Consultants |
| .HK5 | Swiftpage, Inc. | Tietokantatiedostot | ACT! Database File | Act! | Swiftpage, Inc. |
| .HLD | Autodesk, Inc. | Tietokantatiedostot | Structural Desktop | Autodesk AutoCAD | Autodesk, Inc. |
| .HTRI | Heat Transfer Research, Inc. | Tietokantatiedostot | HTRI Xchanger Suite Data Input File | HTRI Xchanger Suite | Heat Transfer Research, Inc. |
| .HYD | MARIN | Tietokantatiedostot | MARIN Hydrodynamic Database File | Unknown Software | Unknown Developer |
| .IAS | SoftWinter | Tietokantatiedostot | BitDefender Data File | BitDefender | Bitdefender |
| .IBD | Oracle Corporation | Tietokantatiedostot | MySQL InnoDB Database Table | MySQL | Oracle Corporation |
| .IDB | Microsoft Corporation | Tietokantatiedostot | Visual Studio Intermediate Debug File | Microsoft Visual Studio | Microsoft Corporation |
| .INQ | Queensgate Systems | Tietokantatiedostot | Internet Query Configuration File | Piped | Queensgate Systems |
| .ITW | Prairie Group | Tietokantatiedostot | InTouch With Database File | Prairie Group InTouch With | Prairie Group |
| .IVD | Bitdefender | Tietokantatiedostot | Incremental Virus Definitions File | Bitdefender Total Security 2018 | Bitdefender |
| .IWC | Felipe Sánchez | Tietokantatiedostot | Installwatch Database File | InstallWatch | Felipe Sánchez |
| .IX2 | Corel | Tietokantatiedostot | WordPerfect Address Book | Corel WordPerfect X8 | Corel |
| .JET | Microsoft Corporation | Tietokantatiedostot | JET Database File | Microsoft Access | Microsoft Corporation |
| .JST | Jabosoft | Tietokantatiedostot | Jnes Save State | Jnes | Jabosoft |
| .JTX | Microsoft Corporation | Tietokantatiedostot | XPS Document File | Microsoft XPS Viewer | Microsoft Corporation |
| .JZ | Unknown Developer | Tietokantatiedostot | JamesZhu Internet Browser Database | JamesZhu Internet Browser | Unknown Developer |
| .K01 | SoftVelocity | Tietokantatiedostot | Clarion Database Key | Clarion | SoftVelocity |
| .K03 | SoftVelocity | Tietokantatiedostot | Clarion Database Key | Clarion | SoftVelocity |
| .K04 | SoftVelocity | Tietokantatiedostot | Clarion DOS Database Key File | Clarion | SoftVelocity |
| .K07 | SoftVelocity | Tietokantatiedostot | Clarion Database Key | Clarion | SoftVelocity |
| .KDB | Open Source | Tietokantatiedostot | KeePass Database File | KeePass Password Safe | Open Source |
| .KDH | National Project Research Center of CD | Tietokantatiedostot | Chinese Academic Journals Online Full-Text Database | CNKI CAJViewer | National Project Research Center of CD |
| .KPD | Kaspersky Lab | Tietokantatiedostot | Kaspersky Lab Application Description | Kaspersky Anti-Virus | Kaspersky Lab |
| .KV3 | KYOCERA MITA Europe | Tietokantatiedostot | KM-NET Viewer Database | KM-NET Viewer | KYOCERA MITA Europe |
| .LCR | NEC Corporation | Tietokantatiedostot | NEC Electra Elite LCR Customer Database | NEC Electra Elite LCR | NEC Corporation |
| .LCT | Oracle Corporation | Tietokantatiedostot | Oracle Database Configuration File | Oracle Database | Oracle Corporation |
| .LD1 | dBase, LLC | Tietokantatiedostot | dBASE Overlay File | dBASE™ PLUS 12 | dBase, LLC |
| .LGC | Microsoft Corporation | Tietokantatiedostot | Microsoft Windows Application Log File | Microsoft Windows | Microsoft Corporation |
| .LJB | Harman International Industries | Tietokantatiedostot | Lightjockey Database | Lightjockey | Harman International Industries |
| .LNK | Microsoft Corporation | Tietokantatiedostot | Windows File Shortcut | Microsoft Windows | Microsoft Corporation |
| .LUTX | Lutron Electronics Co., Inc | Tietokantatiedostot | RadioRA 2 Essentials Project Database | Lutron Electronics RadioRA Essentials | Lutron Electronics Co., Inc |
| .LUX | Coloritto | Tietokantatiedostot | Spectramap Database | Spectramap | Coloritto |
| .LZD | Christopher J. Madsen | Tietokantatiedostot | Binary Difference File | VBinDiff | Christopher J. Madsen |
| .MAF | National Cancer Institute | Tietokantatiedostot | Mutation Annotation Format File | Microsoft Notepad | Microsoft Corporation |
| .MAQ | Microsoft Corporation | Tietokantatiedostot | Microsoft Access Query | Microsoft Access | Microsoft Corporation |
| .MAR | Microsoft Corporation | Tietokantatiedostot | Microsoft Access Report | Microsoft Access | Microsoft Corporation |
| .MAS | Image Space Incorporated | Tietokantatiedostot | rFactor Track File | Image Space rFactor | Image Space Incorporated |
| .MAV | Microsoft Corporation | Tietokantatiedostot | Access View File | Microsoft Access | Microsoft Corporation |
| .MAW | Microsoft Corporation | Tietokantatiedostot | Access Data Access Page | Microsoft Access | Microsoft Corporation |
| .MDB | Microsoft Corporation | Tietokantatiedostot | Microsoft Access Database | SAS | SAS Institute Inc. |
| .MDBHTML | Microsoft Corporation | Tietokantatiedostot | Microsoft Access Database HTML File | Microsoft Access | Microsoft Corporation |
| .MDF | Alcohol Soft | Tietokantatiedostot | Alcohol 120% Disk Image File Format | IsoBuster | Smart Projects |
| .MDN | Microsoft Corporation | Tietokantatiedostot | Blank Access Database Template | Microsoft Access | Microsoft Corporation |
| .MDT | Microsoft Corporation | Tietokantatiedostot | Microsoft Access Data File | Microsoft Access | Microsoft Corporation |
| .MDX | Disc Soft Ltd. | Tietokantatiedostot | Extended Media Descriptor File | DAEMON Tools | Disc Soft Ltd. |
| .MER | Rockwell Automation Inc. | Tietokantatiedostot | RSView Development Runtime File | Rockwell Automation RSView Studio or RSView ME | Rockwell Automation Inc. |
| .MFD | Yamaha Corporation | Tietokantatiedostot | Music Finder Database | MusicFinderView | PSR Tutorial |
| .MGN | Interscape | Tietokantatiedostot | Modern Genealogy Database File | Modern Genealogy | Interscape |
| .MIB | Milenix Software Ltd. | Tietokantatiedostot | MyInfo Topic Backup | MyInfo | Milenix Software Ltd. |
| .MMO | Memory-Map | Tietokantatiedostot | Memory Map Overlay File | Memory-Map Navigator | Memory-Map |
| .MPB | FJ Soft | Tietokantatiedostot | MyPhoneExplorer Backup File | MyPhoneExplorer | FJ Soft |
| .MPC | Open Source | Tietokantatiedostot | Musepack Compressed Audio File | VLC Media Player | VideoLAN |
| .MPD | Microsoft Corporation | Tietokantatiedostot | Microsoft Project Database | Microsoft Office | Microsoft Corporation |
| .MRG | Interscape | Tietokantatiedostot | Now Contact Merge Template | Now Up-to-Date (Now Contact) | Now Software |
| .MTC | Make The Cut, LLC | Tietokantatiedostot | Make The Cut! Project | Make the Cut! | Make The Cut, LLC |
| .MTW | Minitab Inc | Tietokantatiedostot | Minitab Worksheet File | Minitab | Minitab Inc |
| .MUD | Autodesk, Inc. | Tietokantatiedostot | Mudbox 3D Scene File | Autodesk Mudbox 2017 | Autodesk, Inc. |
| .MWB | MySQL AB | Tietokantatiedostot | MySQL Workbench Document | MySQL Workbench | Oracle Corporation |
| .MYD | MySQL AB | Tietokantatiedostot | MySQL Database Data File | MySQL | Oracle Corporation |
| .NDF | Microsoft Corporation | Tietokantatiedostot | SQL Server Secondary Database File | Microsoft SQL Server | Microsoft Corporation |
| .NE3 | OM2 Services LLC | Tietokantatiedostot | OM2 OMALI NENA Document | OM2 OMALI Professional | OM2 Services LLC |
| .NNT | Qualcomm | Tietokantatiedostot | Eudora Address Book File | QUALCOMM Eudora | Qualcomm |
| .NS3 | IBM | Tietokantatiedostot | Lotus Notes 3 Database | IBM Lotus Notes | IBM |
| .NS4 | IBM | Tietokantatiedostot | Lotus Notes 4 Database | IBM Lotus Notes | IBM |
| .NSF | Unknown Developer | Tietokantatiedostot | NES Sound Format File | DeliPlayer | Open Source |
| .NSG | IBM | Tietokantatiedostot | Lotus Notes Database | IBM Lotus Notes | IBM |
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