| .F | The Eclipse Foundation | Pliki z danymi | Fortran Source Code | MacroMates TextMate | MacroMates |
| .F#+A | RagTime.de Development | Pliki z danymi | RagTime Classic File | RagTime | RagTime.de Development |
| .F#+D | RagTime.de Development | Pliki z danymi | RagTime Classic File | RagTime | RagTime.de Development |
| .F01 | U.S. Army Corps of Engineers | Pliki z danymi | HEC-RAS Flow File | HEC-RAS | U.S. Army Corps of Engineers |
| .F03 | The Eclipse Foundation | Pliki z danymi | Fortran Source Code | MacroMates TextMate | MacroMates |
| .F04 | U.S. Army Corps of Engineers | Pliki z danymi | HEC-RAS Flow File | HEC-RAS | U.S. Army Corps of Engineers |
| .F05 | U.S. Army Corps of Engineers | Pliki z danymi | HEC-GeoRAS Flow Data | HEC-RAS | U.S. Army Corps of Engineers |
| .F15 | BALARAD | Pliki z danymi | Embird Embroidery Software Data | Embird Embroidery Software | BALARAD |
| .F2 | ASUS | Pliki z danymi | Biosflash File | Windows BIOS Flash Utility | ASUS |
| .F2F | Byteworx | Pliki z danymi | Byteworx FMEA Exported Data File | Byteworx FMEA | Byteworx |
| .F3D | Autodesk, Inc. | Pliki z danymi | Fusion 3D Design | Autodesk Fusion 360 | Autodesk, Inc. |
| .F3G | GIGABYTE | Pliki z danymi | GIGABYTE BIOS Update | GIGABYTE Firmware Update Utility | GIGABYTE |
| .F4F | Adobe Systems Incorporated | Pliki z danymi | Adobe HTTP Dynamic Streaming Segment | Adobe Flash Player | Adobe Systems Incorporated |
| .F4G | GIGABYTE | Pliki z danymi | GIGABYTE BIOS Update | GIGABYTE Firmware Update Utility | GIGABYTE |
| .F6G | GIGABYTE | Pliki z danymi | GIGABYTE BIOS Update | GIGABYTE Firmware Update Utility | GIGABYTE |
| .FA | Nucleobytes | Pliki z danymi | FASTA Formatted Sequence File | SnapGene | GSL Biotech LLC |
| .FAC | Newera Software Technology, Inc. | Pliki z danymi | FACE Graphic File | Graphics Converter Pro | Newera Software Technology, Inc. |
| .FAF | Thomas Tempelmann | Pliki z danymi | Find Any File Search Description | Find Any File | Thomas Tempelmann |
| .FAMILYFILE | Leister Productions | Pliki z danymi | Reunion Family Tree File | Reunion | Leister Productions |
| .FAS | Autodesk, Inc. | Pliki z danymi | Compiled Fast-Load AutoLISP File | Autodesk AutoCAD | Autodesk, Inc. |
| .FAST | Apple | Pliki z danymi | Golden Orchard Apple II CD Rom File | Apple OS X | Apple |
| .FASTA | Nucleobytes | Pliki z danymi | FASTA Sequence File | SnapGene | GSL Biotech LLC |
| .FASTQ | Technelysium | Pliki z danymi | FASTQ Format | Notepad++ | Don Ho |
| .FAZ | Tandy | Pliki z danymi | DeskMate Generic Character Data File | DeskMate | Tandy |
| .FB5 | Tranzsoft Group Limited | Pliki z danymi | FlowBiz Integrator File | FlowBiz | Tranzsoft Group Limited |
| .FBF | Promosoft Corporation | Pliki z danymi | Free Backup Fix Backup File | Promosoft Free Backup Fix | Promosoft Corporation |
| .FBK | Microsoft Corporation | Pliki z danymi | Microsoft Dynamics NAV Backup File | Microsoft Dynamics NAV (Navision) | Microsoft Corporation |
| .FBR | Blueberry Software | Pliki z danymi | FlashBack Screen Recording | Blueberry FlashBack | Blueberry Software |
| .FBS | Interscape | Pliki z danymi | Fastbid Plan Sheet | Fastbid | Interscape |
| .FBV | VSoft Technologies | Pliki z danymi | FinalBuilder Persistent Variables File | FinalBuilder | VSoft Technologies |
| .FC | OpenText | Pliki z danymi | FirstClass Settings File | OpenText FirstClass | OpenText |
| .FC7 | Evolution Computing | Pliki z danymi | FastCAD Version 7 Drawing | FastCAD | Evolution Computing |
| .FCA | Omnis Software | Pliki z danymi | Omnis Web Client File | Omnis Studio | Omnis Software |
| .FCB | Interscape | Pliki z danymi | FAAST Builder Data | FAAST Builder | Interscape |
| .FCH | Gaussian, Inc. | Pliki z danymi | Gaussian Checkpoint File | Gaussian | Gaussian, Inc. |
| .FCHK | Gaussian, Inc. | Pliki z danymi | Gaussian Checkpoint | Gaussian | Gaussian, Inc. |
| .FCI | Geognostics | Pliki z danymi | EROSION 3D Inflow Table | Erosion 3D | Geognostics |
| .FCM | fcraft.net | Pliki z danymi | fCraft World File | fCraft | fcraft.net |
| .FCR | Michigan Department of Community Health | Pliki z danymi | Cost Report Data File | Electronic Cost Report for Microsoft Excel | Michigan Department of Community Health |
| .FCS | Interscape | Pliki z danymi | Flow Cytometry Standard File | Verity Software House V-Comp | Interscape |
| .FCT | Salty Brine | Pliki z danymi | FolderClone Task List | Salty Brine FolderClone | Salty Brine |
| .FCW | Evolution Computing | Pliki z danymi | FastCAD Windows Drawing | IMSI TurboCAD Deluxe | Redway3d and others |
| .FD | Data Access Worldwide | Pliki z danymi | DataFlex Data File | DataFlex | Data Access Worldwide |
| .FDA | Relic Entertainment | Pliki z danymi | Dawn Of War Audio File | Relic Entertainment Dawn of War | Relic Entertainment |
| .FDB | Extensis | Pliki z danymi | Portfolio Catalog | Portfolio | Extensis |
| .FDC | Autodesk, Inc. | Pliki z danymi | AutoCAD Field Catalog File | Autodesk AutoCAD | Autodesk, Inc. |
| .FDE | Ternion Corporation | Pliki z danymi | FLAMES Dataset Export File | FLAMES | Ternion Corporation |
| .FDK | Interscape | Pliki z danymi | Fluentizer Fluent Dictionary | Fluentizer | Interscape |
| .FDL | Corel Corporation | Pliki z danymi | Corel Paradox Secondary Index | Corel WordPerfect X8 | Corel |
| .FDM | Microsoft Corporation | Pliki z danymi | Exchange Forms Designer Form Message | Microsoft Exchange Server | Microsoft Corporation |
| .FDS | Adobe Systems Incorporated | Pliki z danymi | JetForm FormFlow Data File | JetForm FormFlow | Adobe Systems Incorporated |
| .FDT | Final Draft | Pliki z danymi | Final Draft 5-7 Template | Final Draft | Final Draft |
| .FDX | Final Draft | Pliki z danymi | Final Draft Document | Final Draft | Final Draft |
| .FED | RK SOFTWARE | Pliki z danymi | FormEdik Form Data | FormEdik | RK SOFTWARE |
| .FEED | JRiver | Pliki z danymi | JRiver Media Center Data | JRiver Media Center | JRiver |
| .FEM | DHI | Pliki z danymi | FEFLOW FEM Problem | FEFLOW | DHI |
| .FENDER | Apple | Pliki z danymi | Golden Orchard Apple II CD Rom File | Apple OS X | Apple |
| .FEP | Microsoft Corporation | Pliki z danymi | WEFT Embedding Project | Web Embedding Fonts Tool (WEFT) | Microsoft Corporation |
| .FES | G&A M.C. | Pliki z danymi | Fileless Occurrence Placeholder | Topicscape | G&A M.C. |
| .FET | Volker Dirr | Pliki z danymi | Free Timetabling Software Data | FET - Free Timetabling Software | Volker Dirr |
| .FEX | Information Builders | Pliki z danymi | WebFOCUS FOCUS Web390 Procedure Data | WebFOCUS | Information Builders |
| .FF1 | Page Technology Marketing, Inc | Pliki z danymi | PCLTool File | PCLTool | Page Technology Marketing, Inc |
| .FF2 | AceBIT | Pliki z danymi | Hello Engines! | Hello Engines | Interscape |
| .FFBEAUTY | Reallusion, Inc. | Pliki z danymi | FaceFilter File | FaceFilter | Reallusion, Inc. |
| .FFBLUSH | Reallusion, Inc. | Pliki z danymi | FaceFilter Blush File | FaceFilter | Reallusion, Inc. |
| .FFC | Westboro Photonics | Pliki z danymi | Westboro Photonics Flat Field Correction Data | Photometrica | Westboro Photonics |
| .FFD | Microsoft Corporation | Pliki z danymi | SharePoint FFDDumper Log | Microsoft Notepad | Microsoft Corporation |
| .FFDATA | ABBYY | Pliki z danymi | ABBYY Eform Document | ABBYY FineReader | ABBYY |
| .FFF | Hasselblad | Pliki z danymi | Hasselblad RAW Image | Microsoft Windows Photos | Microsoft Corporation |
| .FFO | Microsoft Corporation | Pliki z danymi | Find Fast Document Properties Cache | Microsoft Outlook | Microsoft Corporation |
| .FFT | Adobe Systems Incorporated | Pliki z danymi | Adobe Audition Noise Print File | Adobe Audition | Adobe Systems Incorporated |
| .FFW | Festo | Pliki z danymi | Festo Firmware File | FCT | Festo |
| .FFWP | Lucom GmbH | Pliki z danymi | FormsForWeb Packet | FormsForWeb Filler | Lucom GmbH |
| .FGD | Valve | Pliki z danymi | Forge Game Data File | Valve Source SDK | Valve |
| .FGT | Open Source | Pliki z danymi | FreeGant Skeleton | FreeGant Skeleton | Open Source |
| .FHC | Canute LLP | Pliki z danymi | FHC Data File | Canute FHC | Canute LLP |
| .FHQ | Simon Orde | Pliki z danymi | Family Historian Query | Family Historian | Simon Orde |
| .FHR | Simon Orde | Pliki z danymi | Family Historian Query | Family Historian | Simon Orde |
| .FI | Microsoft Corporation | Pliki z danymi | Fortran Interface Data | Fortran | IBM |
| .FID | Microsoft Corporation | Pliki z danymi | Windows Indexing Service File | Microsoft Windows | Microsoft Corporation |
| .FIG | Open Source | Pliki z danymi | Xfig Drawing | Winfig | Andreas Schmidt |
| .FIH | Forensic Innovations | Pliki z danymi | File Investigator Data | File Investigator | Forensic Innovations |
| .FIL | dBase, LLC | Pliki z danymi | Files List Object File | dBase | dBase, LLC |
| .FILELOC | Apple | Pliki z danymi | Apple Finder Internet Location Data | Apple OS X | Apple |
| .FILES | Apple | Pliki z danymi | Golden Orchard Apple II CD Rom File | Apple OS X | Apple |
| .FILTER | Apple | Pliki z danymi | Golden Orchard Apple II CD Rom File | Apple OS X | Apple |
| .FIM | Terry W Gintz and Jules Ruis | Pliki z danymi | Fractal Imaginator Data Or Parameter | Fractal Imaginator | Terry W Gintz and Jules Ruis |
| .FIN | Interscape | Pliki z danymi | Sapir Torah Text | Sapir Torah | Interscape |
| .FINAL | Apple | Pliki z danymi | Golden Orchard Apple II CD Rom File | Apple OS X | Apple |
| .FIP | Forensic Innovations, Inc. | Pliki z danymi | RobWare File Investigator | File Investigator | Forensic Innovations |
| .FIR | Canon Inc. | Pliki z danymi | Canon Digital Camera EOS Firmware | Canon EOS Digital Cameras | Canon Inc. |
| .FIRMWARE | Würth Online World GmbH | Pliki z danymi | WOW! Firmware File | WOW! | Würth Online World GmbH |
| .FISH | Unknown Developer | Pliki z danymi | 3D Fish Tank File | Unknown Software | Unknown Developer |
| .FIX | Corey Zeke Womack (Torrunt) | Pliki z danymi | Vimage Image File | Vimage | Corey Zeke Womack (Torrunt) |
| .FJG | One Identity | Pliki z danymi | Identity Manager Process File | Identity Manager | One Identity |
| .FJL | Symantec Corporation | Pliki z danymi | Rootkit.Win32.Agent.fjl Virus File | AVG Antivirus | AVG Technologies |
| .FJSW | Hermitech Laboratory | Pliki z danymi | Formulator Tarsia Jigsaw Puzzle | Formulator Tarsia | Hermitech Laboratory |
| .FKD | LANSRAD | Pliki z danymi | FotoKiss Photo Set Data File | FotoKiss | LANSRAD |
| .FKT | KDE | Pliki z danymi | KmPlot Data File | KmPlot | KDE |
| .FLB | FileMaker Inc. | Pliki z danymi | FileMaker Pro Label File | FileMaker Pro | FileMaker Inc. |
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