| fcl | FidoCAD Library |
| fcm | Brother ScanNCut Data |
| fcm | Factory Commander Model Data |
| fcm | FCEUX FCE-Ultra Capture Movie |
| fcm | FidoCAD Macro Data |
| fcod | Adobe PageMaker Filter Data |
| fcp | FLAMES Checkpoint Restart Data |
| fcpcache | Final Cut Pro Cache Data |
| fcpevent | Final Cut Pro Event Data |
| fcpxdest | Final Cut Pro Share Destination Data |
| fcs | Canon ZoomBrowser EX Data |
| fcs | Faircom c-treeACE Server Data |
| fcs | FCEUX Saved State |
| fcs | Flow Cytometry Standard Data |
| fcs | Rapidform Polygon Faces Data |
| fcst | Delft-FEWS Forecast Data |
| fct | Campaign Cartographer Data |
| fct | FolderClone Task List |
| fcw | Campaign Cartographer v2 Data |
| fcxr | FileCapsule Deluxe Data |
| fcxu | FileCapsule Deluxe Data |
| fcz | Poser Compressed Face Data |
| fd | DataFlex Data File |
| fd | LaTeX Font Definition Data |
| fd | STK Facility Database Main File |
| fd1 | Windows Live Photo Gallery Thumbnail Database |
| fdat | Fiasco Database Data File |
| fdata | NONMEM Data |
| fdb | Art Explosion Image Catalog Database |
| fdb | Firebird SQL Database |
| fdb | FormTool Pro Form Data |
| fdb | Microsoft Dynamics NAV Database |
| fdb | Navision Financials Database |
| fdb | Portfolio Catalog Data |
| fdc | Autodesk AutoCAD Fields Description |
