| Extension | Summary |
|---|
| .F | Fortran Source Code |
| .F04 | Nastran Execution Summary File |
| .F06 | Nastran Output File |
| .F2K | Fortran Source Code File |
| .F2R | Farandole Linear Module File |
| .F32 | Raw 32-Bit Audio File |
| .F3D | Fusion 360 Archive File |
| .F3F | Crazy Machines Font File |
| .F3R | Farandoyle Blocked Module File |
| .F3Z | Fusion 360 Shared Project Archive |
| .F4A | Adobe Flash Protected Audio File |
| .F4F | Flash Video Fragment |
| .F4M | Adobe Flash Media Manifest File |
| .F4P | Adobe Flash Protected Media File |
| .F4V | Flash MP4 Video File |
| .F64 | Raw 64-Bit Audio File |
| .F90 | Fortran 90 Source Code File |
| .F95 | Fortran 95 Source Code File |
| .FA | FASTA Formatted Sequence File |
| .FAC | FACE Image File |
| .FACE | FACE Graphic File |
| .FACEFX | FaceFX Actor File |
| .FACEFX_INGAME | FaceFX In-Game Actor File |
| .FACES | JavaServer FacesServlet Pointer |
| .FADEIN | Fade In Document |
| .FADEIN.TEMPLATE | Fade In Template |
| .FAL | Bitmap Graphic Header Information |
| .FAMILYFILE | Reunion Family File |
| .FAN | Finale Font Annotation File |
| .FAP | PARIS Audio File |
| .FAQ | Frequently Asked Questions Document |
| .FAR | The Sims Archive File |
| .FAS | QuickSilver Fast Save Lisp File |
| .FASTA | FASTA Sequence File |
| .FAT | Zinf Theme File |
| .FAVORITEMETADATA | Transmit Favorites Data File |
| .FAX | Now Contact Fax Template |
| .FB! | FlashGet Incomplete Download File |
| .FB2 | FictionBook 2.0 File |
| .FB2K-COMPONENT | Foobar2000 Component Install File |
| .FBC | Family Tree Maker for DOS Backup File |
| .FBF | Free Backup Fix Backup File |
| .FBK | Family Tree Maker for Windows Backup File |
| .FBL | iGO Map File |
| .FBM | Marine Vessel Model File |
| .FBP | wxFormBuilder Project |
| .FBP7 | FinalBuilder 7 Project |
| .FBQ | Trine 2 Data File |
| .FBR | Mercury Screen Recording |
| .FBRB | Battlefield Bad Company 2 Data File |
| .FBT | ABBYY FineReader Document Options File |
| .FBU | FEBE Firefox Backup File |
| .FBW | HP Recovery Manager Backup File |
| .FBX | Autodesk FBX Interchange File |
| .FBZ | FlashBack Screen Recorder Movie |
| .FBZ7 | Compressed FinalBuilder 7 Project |
| .FC | Paradise Ransomware Encrypted File |
| .FC1 | FCEUX Save State File |
| .FC2 | Poser Face Pose File |
| .FC2MAP | Far Cry 2 User Map |
| .FCARCH | Final Cut Pro Archive |
| .FCC | Forms Credential Collector File |
| .FCD | Virtual CD Format |
| .FCDT | FormsCentral Design Template |
| .FCE | ForeUI Custom Element File |
| .FCF | Final Draft Converter File |
| .FCGI | FastCGI File |
| .FCL | ForeUI Custom Library File |
| .FCM | fCraft World File |
| .FCP | FontCreator Project |
| .FCPBUNDLE | Final Cut Pro Library |
| .FCPEVENT | Final Cut Pro Event File |
| .FCPPROJECT | Final Cut Pro Project File |
| .FCPROJECT | Final Cut Pro X Project File |
| .FCPXDEST | Final Cut Pro Share Destination File |
| .FCPXML | Final Cut Pro XML File |
| .FCS | FCEUX Save State File |
| .FCSTD | FreeCAD Document |
| .FCSTD1 | FreeCAD Backup Document |
| .FCT | FolderClone Task List |
| .FCW | FastCAD Windows Drawing |
| .FCZ | Compressed Poser Face Pose File |
| .FD | DataFlex Data File |
| .FD2 | PictureMate Borders File |
| .FDA | Dawn of War Audio File |
| .FDB | Microsoft Dynamics NAV Database File |
| .FDC | AutoCAD Field Catalog File |
| .FDD | Parallels Desktop Floppy Disk Image File |
| .FDF | Origin Fitting Function Definition File |
| .FDI | Amiga Disk Image |
| .FDM | Exchange Forms Designer Form Message |
| .FDMDOWNLOAD | Free Download Manager Partially Downloaded File |
| .FDP | MySafe Encrypted Data |
| .FDR | Windows Error Report File |
| .FDS | FME Custom Format File |
| .FDT | FormDocs Template |
| .FDX | Food Data Exchange File |
| .FDXT | Final Draft 8 Template |
| .FEA | AFDKO Feature Definitions File |
| .FEATURE | SharePoint Feature File |
| .FEEDBACK | Expression SketchFlow Feedback File |
| .FES | Fileless Occurrence Placeholder |
| .FETCHMIRROR | Fetch Mirror Document |
| .FETCHSHORTCUTS | Fetch Shortcut List FIle |
| .FEV | FLAMES Environment Variable File |
| .FEY | FCS Express Layout File |
| .FE_LAUNCH | FCS Express Launch File |
| .FF | Call of Duty 4 Fast File |
| .FF7CCMODEL | Crisis Core: Final Fantasy VII Model |
| .FFA | Find Fast Status File |
| .FFD | FATE Saved Game |
| .FFF | Hasselblad RAW Image |
| .FFIL | Mac Font Suitcase |
| .FFINDEX | FFmpegSource2 Media Index |
| .FFL | Fetion Emoticons Package |
| .FFM | FFmpeg Stream File |
| .FFO | Find Fast Document Properties Cache |
| .FFS | FME Desktop Feature Store File |
| .FFT | Adobe Audition Noise Print File |
| .FFU | Full Flash Update Image File |
| .FFWP | FormsForWeb Packet |
| .FFX | After Effects Preset File |
| .FG | FaceGen Project File |
| .FG3 | FX Graph 3 File |
| .FGC | Greeting Card Factory Card File |
| .FGD | Forge Game Data File |
| .FGL | Fifth Generation Language Source File |
| .FGS | Fig Figure Settings File |
| .FH | Symantec Backup Exec File |
| .FH10 | FreeHand 10 Drawing File |
| .FH11 | FreeHand 11 Drawing File |
| .FH3 | FreeHand 3 Drawing File |
| .FH4 | FreeHand 4 Drawing File |
| .FH5 | FreeHand 5 Drawing File |
| .FH6 | FreeHand 6 Drawing File |
| .FH7 | FreeHand 7 Drawing File |
| .FH8 | FreeHand 8 Drawing File |
| .FH9 | FreeHand 9 Drawing File |
| .FHC | FHC Data File |
| .FHD | FreeHand Drawing File |
| .FHF | Free Hide Folder Backup File |
| .FIC | WinDev Hyper File Database |
| .FID | Microsoft Catalog Indexing Service File |
| .FIF | Fractal Image File |
| .FIG | Xfig Drawing |
| .FIL | Symbian Application Logo File |
| .FILA | Aleph One Replay File |
| .FILE | Generic Windows File |
| .FILEBOLT | Filebolt Encrypted File |
| .FILM | Filmkey Player Media File |
| .FILM_CPK | Sega FILM Multimedia File |
| .FILTERS | Visual C++ Project Filters File |
| .FIMPP | FiM++ Source Code File |
| .FINGNET | Overlook Fing Saved Network File |
| .FIRM | Boot9Strap 3DS Firmware File |
| .FIT | Garmin Activity File |
| .FITS | Flexible Image Transport System File |
| .FKB | Flipkart eBook File |
| .FKY | FoxPro Macro |
| .FL | Freelancer Saved Game File |
| .FL1 | Lenovo BIOS Update File |
| .FL3 | Flash 3D File |
| .FLA | Adobe Animate Animation |
| .FLAC | Free Lossless Audio Codec File |
| .FLAM3 | Fractal Flames File |
| .FLAME | Fractal Flames File |
| .FLASH | Frictional Games Flashback File |
| .FLASK | FlasKMPEG Settings Profile |
| .FLATPAK | Linux Flatpak Application Bundle |
| .FLATPAKREF | Linux Flatpak Application Package |
| .FLATPAKREPO | Linux Flatpak Repository |
| .FLB | FileMaker Pro Label File |
| .FLC | FLIC Animation |
| .FLD | YSFLIGHT Field File |
| .FLEXOLIBRARY | Final Cut Pro Library Database |
| .FLF | Microsoft Dynamics NAV License File |
| .FLG | IsoPuzzle Flag File |
| .FLH | FLIC Animation File |
| .FLI | FLIC Animation |
| .FLIC | FLIC Animation |
| .FLIF | Free Lossless Image Format File |
| .FLIPANIM | FlipAnim Project |
| .FLIPCHART | ActivInspire Flipchart File |
| .FLK | AccountEdge Company Lock File |
| .FLKA | Folder Lock Portable Locker File |
| .FLKB | Folder Lock Basic Locker File |
| .FLL | FoxPro Dynamic-Link Library |
| .FLM | FL Studio Mobile Song File |
| .FLO | Automate Flowchart File |
| .FLOW | Expression SketchFlow Data File |
| .FLOWCHART | PureFlow Flowchart |
| .FLOWMAPLIBRARY | Painter Flowmap Library |
| .FLP | Floppy Disk Image |
| .FLR | Flare Decompiled ActionScript File |
| .FLS | ArcView GIS Windows Help Supporting File |
| .FLST | Adobe InDesign Flattener Presets File |
| .FLT | Vue Filters File |
| .FLV | Flash Video File |
| .FLW | Fusion Flow File |
| .FLWA | Folder Lock Wallet File |
| .FLX | FelixCAD Drawing |
| .FM | FileMaker Database |
| .FM2 | FCEUX 2 Movie Capture File |
| .FM3 | Lotus 1-2-3 Spreadsheet Format File |
| .FM5 | FileMaker 5 Database |
| .FMAT | FMAT Runfile |
| .FMC | FormConnect Form File |
| .FME | FME Mapping File |
| .FMELIC | FME License File |
| .FMI | FME Include File |
| .FML | WWE RAW Character File |
| .FMOD | Adobe Illustrator Flattening Module |
| .FMP | AutoCAD Font Map File |
| .FMP12 | FileMaker Pro 12 Database |
| .FMPLUGIN | FileMaker Plug-in |
| .FMPSL | FileMaker Pro 12 Snapshot Link |
| .FMT | FoxPro Format File |
| .FMV | FME Desktop Viewspace File |
| .FMW | FME Workbench File |
| .FMX | FileMaker Plug-in |
| .FMZ | Form•Z Project File |
| .FNBK | Food Network Recipe Manager Data File |
| .FNC | Frogans Player Network Certificate |
| .FND | Windows Saved Search |
| .FNLF | Scarlett Plug-in Suite License File |
| .FNM | Fannie Mae 1003 Data File |
| .FNRECIPES | Food Network Recipe File |
| .FNT | Windows Font File |
| .FNTA | Aleph One Font File |
| .FO | XSL-FO Form |
| .FOB | Dynamics NAV Object Container File |
| .FODP | OpenDocument Flat XML Presentation |
| .FODS | OpenDocument Flat XML Spreadsheet |
| .FODT | OpenDocument Flat XML Document |
| .FOL | PFS First Choice Database File |
| .FOLIO | Adobe Folio File |
| .FOLX | Folx Download File |
| .FOMOD | Fallout Mod Archive |
| .FON | Windows Font Library |
| .FONIX | Fonix Ransomware Encrypted File |
| .FOP | InfoZoom Protected Data File |
| .FOR | Fortran 77 Source File |
| .FORGE | Ubisoft Game Data File |
| .FORM | PreForm Job File |
| .FORTH | Forth Language File |
| .FOS | Fallout 3 Saved Game |
| .FOT | Font Resource File |
| .FOTA | Firmware Over-the-Air File |
| .FOUNTAIN | Fountain Script File |
| .FOX | Furcadia Art File |
| .FP | FileMaker Pro Spreadsheet |
| .FP3 | FileMaker Pro 3 Database |
| .FP4 | FileMaker Pro 4 Database |
| .FP5 | FileMaker Pro 5 Database |
| .FP7 | FileMaker Pro 7+ Database |
| .FP8 | FP8 (= Fast PAQ8) Compressed File |
| .FPA | Finale Performance Assessment File |
| .FPBF | Mac OS X Burn Folder |
| .FPD | Front Panel Designer Project |
| .FPDX | Utilius Fairplay Project |
| .FPE | Free PDF Editor Document |
| .FPENC | FileProtect Encrypted File |
| .FPF | IKEA Home Planner File |
| .FPFV | File Protected From Virus |
| .FPG | FPS Creator Game Project File |
| .FPI | Foxit Reader Plugin |
| .FPID | FPS Creator AI Wizard Data File |
| .FPJ | CryENGINE Facial Editor Project File |
| .FPK | JetForm FormFlow File |
| .FPL | Foobar2000 Playlist File |
| .FPM | FPS Creator Map File |
| .FPMB | FPS Creator Mab Buffer File |
| .FPMO | FPS Creator Map Overlay File |
| .FPOP | Spider-Man: Shattered Dimensions Saved Game |
| .FPOS | Photo Pos Pro Image |
| .FPP | Fortran Source Code |
| .FPPX | Microsoft Fresh Paint Painting File |
| .FPR | Humanize Preset File |
| .FPS | FPS Creator Segment File |
| .FPSL | FileMaker Pro Snapshot Link |
| .FPSX | Nokia Firmware Format File |
| .FPT | Alpha Five Table Memo File |
| .FPX | FlashPix Bitmap Image File |
| .FQC | FAQ Creator File |
| .FR3 | FastReport Form File |
| .FRAMES | xScope Frames File |
| .FRAMESET | Frame Painter for LGS Frame Set File |
| .FRAMEWORK | Mac OS X Application Framework |
| .FRC | Mandelbrot Explorer Color Settings File |
| .FRD | Frequency Response Data File |
| .FRDOC | FineReader Document |
| .FREECELLSAVE-MS | Microsoft FreeCell Saved Game |
| .FREEWAY | Freeway Document |
| .FRF | Free Report Form File |
| .FRG | Sound Forge Pro Project File |
| .FRJ | FreeForm-J Project File |
| .FRK | Macintosh Resource or Data Fork |
| .FRL | Electronic Form Loader File |
| .FRM | Form File |
| .FRO | dBASE IV Compiled Report |
| .FRR | Mandelbrot Explorer Fractal Region Settings File |
| .FRS | Flash Renamer Script |
| .FRT | FoxPro Report Memo |
| .FRW | RollerCoaster Tycoon 3 Fireworks Effects File |
| .FRX | FoxPro Report |
| .FRY | fryrender Scene File |
| .FRZ | Locked FormFlow File |
| .FS | Visual F# Source File |
| .FS2 | FreeSpace 2 Saved Mission File |
| .FSA | Fragment Analysis Data File |
| .FSB | Form•Z Compiled Script |
| .FSC | FL Studio Score File |
| .FSD | Flowsheet Document |
| .FSG | FreeCol Saved Game File |
| .FSH | Fragment Shader File |
| .FSI | Visual F# Signature File |
| .FSIF | MyLabel Designer Deluxe Data File |
| .FSL | Form•Z Script |
| .FSM | Splitty Master Split File |
| .FSPROJ | FireStarter Project File |
| .FSPY | fSpy Project |
| .FSQ | CryENGINE Facial Editor Sequence File |
| .FSS | Splitty Data Split File |
| .FSSAVE | Flight Simulator Save File |
| .FSSCRIPT | Visual F# Script |
| .FST | FL Studio State File |
| .FSTAB | File Systems Table File |
| .FSX | Visual F# Script File |
| .FT | Edgecam Feature Template |
| .FT10 | FreeHand 10 Drawing Template |
| .FT11 | FreeHand 11 Drawing Template |
| .FT7 | FreeHand 7 Drawing Template |
| .FT8 | FreeHand 8 Template |
| .FT9 | FreeHand 9 Drawing Template |
| .FTB | Family Tree Builder Genealogy Database File |
| .FTC | Dream League Soccer Asset File |
| .FTF | FlashTool Firmware File |
| .FTG | Full Text Group |
| .FTH | FileMaker Theme File |
| .FTI | FamiTracker Instrument File |
| .FTIL | e-Hastakshar Contract Note |
| .FTL | Fluent Translation List |
| .FTM | Finale Template File |
| .FTMB | Family Tree Maker Backup File |
| .FTMX | Finale Template File |
| .FTN | Fortran Source Code File |
| .FTP | FlashFXP XML File |
| .FTPLOC | FTP Location |
| .FTPQUOTA | Ftpquota File |
| .FTS | Full Text Search |
| .FTW | Family Tree Maker File |
| .FUK | Postal 2 Map File |
| .FUL | Microsoft Backup File List |
| .FUN | Jigsaw Ransomware Encrypted File |
| .FUSE | Adobe Fuse 3D Model |
| .FUZ | Bethesda Softworks Voice File |
| .FVP | File Viewer Plus Batch Presets File |
| .FW | Firmware Update File |
| .FWACTION | Freeway Action File |
| .FWACTIONB | Freeway Action Bundle File |
| .FWBACKUP | Freeway Backup |
| .FWD | RollerCoaster Tycoon 3 Fireworks Display File |
| .FWDICT | Freeway User Dictionary File |
| .FWDN | fWriter Document |
| .FWP | Microsoft Expression Web Package |
| .FWT | FacetWin Configuration File |
| .FWTB | Freeway Template Bundle |
| .FWTEMPLATE | Freeway Template |
| .FWTEMPLATEB | Freeway Template Bundle |
| .FX | ReadyBoot Trace File |
| .FXA | OC3 Entertainment FaceFX Actor File |
| .FXB | FX Bank File |
| .FXC | FilePackager Configuration |
| .FXCPROJ | FX Composer Project File |
| .FXF | BigFix Action File |
| .FXG | Flash XML Graphics File |
| .FXL | FaceFX Language File |
| .FXM | WinFax Document |
| .FXML | FXML Source Code File |
| .FXP | FX Preset File |
| .FXPL | Adobe Flash FXP Library |
| .FXS | messiahStudio Scene File |
| .FXT | Finale Plug-in |
| .FZ | Fritzing Project File |
| .FZA | Form•Z Autosave File |
| .FZB | Form•Z Project Backup File |
| .FZBZ | Fritzing Bundled Bin File |
| .FZF | Casio FZ-1 Full Dump |
| .FZIP | Foxit Reader Add-on |
| .FZM | Fritzing Module File |
| .FZP | Form•Z Plug-in |
| .FZPZ | Fritzing Part File |
| .FZV | Casio FZ-1 Voice Dump |
| .FZZ | Fritzing Shareable Project File |