| Abbreviation | Definition |
|---|---|
| FLX | Compiled binary (DataFlex) |
| FLX | Database (Flexstor format) |
| FM | FileMaker Pro Database file |
| FM1 | Spreadsheet (Lotus 1-2-3 release 2.x) |
| FM3 | Harvard Graphics 3.0 Device driver |
| FM3 | Spreadsheet (Lotus 1-2-3 release 3.x) |
| FMB | WordPerfect for Windows File Manager Button bar |
| FMF | Font or icon file (IBM LinkWay) |
| FMK | Makefile (Fortran PowerStation) |
| FMO | dBASE IV Compiled format file Object code |
| FMP | FLAMES model prototype file (Ternion Corporation) |
| FMPP | FLAMES model prototype file (Ternion Corporation) |
| FMT | Fast loading format (TeX) |
| FMT | Format file (dBASE IV - FoxPro - Clipper 5 - dBFast - Gate3) |
| FMT | Style sheet (Sprint) |
| FMV | Full Motion Video file |
| FN3 | Harvard Graphics 3.0 Font file |
| FND | Windows 95 items FouND Saved search file |
| FNT | Font file (many) |
| FNX | Inactive font (Exact) |