| ffe | Microsoft DirectInput Force Feedback Effect |
| fgd | Valve Hammer Forge Game Data |
| fgl | FGL Source Code |
| fi | Fortran Interface File |
| fi | Gforth Image File |
| fic | WinDev HyperFileSQL Database |
| fig | MATLAB Figure |
| fil | ProWorx NXT Format Export |
| filters | Visual C++ Project Filters |
| fky | Microsoft Visual FoxPro Macro File |
| fla | Shockwave Flash Source File |
| flash | Shockwave Flash Source File |
| fll | Visual FoxPro DLL |
| flm | Flasm Disassembled SWF |
| fly | Fly Script |
| fmb | Oracle Forms Form Module Binary |
| fmo | dBASE IV Compiled Object |
| fmt | Oracle Forms Form Module Text |
| fmx | Oracle Forms Form Module Executable |
| fn | GCL Cross Referencing Data |
| fon | Hitachi Ladder Editor Force File |
| for | Fortran Source Code |
| form | Gambas V2 Form |
| forth | Forth Source Code |
| fox | FoxBase Compiled Executable |
| fpa | Front Panel Express Order Data |
| fpd | Front Panel Express Design |
| fpp | Fortran Source Code |
| fpq | Microsoft Visual FoxPro Updatable Query File |
| fprg | Flowgorithm Program |
| fps | FPS Creator Segment |
| fpt | Visual FoxPro Memo |
| fr3 | FastReport v3 Form |
| frf | FreeReport Form |
| frg | DBase IV Uncompiled Report |
