| flash | Shockwave Flash Source File |
| flb | EasyBuilder Pro Picture Library |
| flbx | EasyBuilder Pro Picture Library |
| fll | Visual FoxPro DLL |
| flm | Flasm Disassembled SWF |
| fly | Fly Script |
| fmb | Oracle Forms Form Module Binary |
| fmdl | Konami Fox Engine Model |
| fmg | Harbour MiniGUI IDE Form |
| fmo | dBASE IV Compiled Object |
| fmt | IAR System Formatting Data |
| fmt | Oracle Forms Form Module Text |
| fmt | Uniface Format Data |
| fmx | Oracle Forms Form Module Executable |
| fn | GCL Cross Referencing Data |
| fo1 | Borland Turbo C Font Data |
| fo2 | Borland Turbo C Font Data |
| fon | Hitachi Ladder Editor Force File |
| footer | WebSTAR Directory Indexer Footer |
| for | Fortran Source Code |
| form | Gambas V2 Form |
| forth | Forth Source Code |
| fox | FoxBase Compiled Executable |
| fp2 | Crestron SIMPL Symbol Mapping Data |
| fpa | Front Panel Express Order Data |
| fpc | FreePascal Compiler Makefile |
| fpd | Front Panel Express Design |
| fpgt | Flowgorithm Program Template |
| fpp | Fortran Source Code |
| fpq | Microsoft Visual FoxPro Updatable Query File |