| fdx | Food Data Exchange File |
| fdxsl2 | FeedDemon Newspaper Style |
| fdxsl4 | FeedDemon Newspaper Style |
| fe | Surface Evolver Data File |
| feb | Sybase PowerDesigner Free Model Backup |
| fee | Precision Fees Data |
| feed | JRiver Media Center Feed Data |
| feed-ms | Microsoft RSS Feed Store |
| fef | Steuer 2001 FEF Data |
| fel | Fugawi Elevation Library Data |
| fem | Algor Simulation FEA Model |
| fem | Sesam GeniE FEM Data |
| fem | Sybase PowerDesigner Free Model |
| fen | Forsyth–Edwards Notation Data |
| fes | Topicscape Fileless Link Export |
| fet | FET Data |
| ffa | Microsoft Find Fast Status File |
| ffblush | FaceFilter Blush Data |
| ffc | Photometrica Flat Field Correction Data |
| ffcmd | Filter Forge Command Data |
| ffdata | Abbyy eFormFiller Data File |
| ffebrow | FaceFilter Eye Brow Data |
| ffeiris | FaceFilter Eye Iris Data |
| ffelash | FaceFilter Eye Lash Data |
| ffeline | FaceFilter Eye Line Data |
| ffeshadow | FaceFilter Eye Shadow Data |
| ffeye | FaceFilter Eye Data |
| fffilter | FaceFilter Filter Data |
| ffhilight | FaceFilter HiLight Data |
| ffindex | FFmpegSource2 Media Index |
| ffiris | FaceFilter Eye Iris Data |
| ffj | FEMFAT Job Data |
| ffl | Microsoft Find Fast List |
| fflip | FaceFilter Lip Data |
| ffmakeup | FaceFilter Makeup Data |