| ffxptheme | FlashFXP Toolbar Theme Data |
| fga | Folder Guard Attributes File |
| fgb | Talysurf CCI 3000 Frame Sequence Data |
| fgd | Folder Guard Data File |
| fgf | Nav.Net NG Fusker Generator Data |
| fgp | Folder Guard Password File |
| fgr | FRSGiftRegistry Data File |
| fgt | FreeGantt Skeleton Data |
| fhb | ForeHelp Backup File |
| fhc | Canute FHC Data FIle |
| fhi | ABINIT FHI Data |
| fhq | Family Historian Query |
| fhr | Family Historian Data |
| fhx | DeltaV Database File |
| fia | FIA Input Data |
| fib | File Investigator Internal Database |
| fid | File Investigator Internal Database |
| fidx | Fiasco Database Index Data |
| fiff | Elekta Neuromag FIFF Data |
| fig | SNES ROM Image FIG |
| fih | File Investigator Internal Database |
| fil | ACL for Windows Data |
| filebolt | Filebolt Encrypted Data |
| fileloc | Mac OS X Finder Internet Location Data |
| filepart | WinSCP Temporary Data |
| fio | Aldus PhotoStyler Graphics Filter |
| fip | File Investigator Internal Database |
| fis | MATLAB Fuzzy Logic Toolbox FIS File |
| fits | HippoDraw FITS Data |
| fiv | File Investigator Internal Database |
| fix | ASL Fixplot Calculated Fixations |
| fjsw | Formulator Tarsia Jigsaw Puzzle |
| fkc | FBackup Catalog File |
| fkd | FotoKiss Photo Set Data |
| fkr | FKR Program Data File |
