| fwl | Firewall Builder Library |
| fwlic | FlexiWrite License Data |
| fwn | FreeWave Network Data |
| fwp | FLAMES Windows Viewer Project |
| fwr | Faceware Analyzer Tracking Data |
| fwt | FTS Network Design Data |
| fx | FastLynx Online Guide |
| fxb | Cubase FX Bank |
| fxf | BigFix Action Data |
| fxf | IBM Endpoint Manager Action |
| fxm | BigFix Fixlet Pool Data |
| fxm | messiahStudio Motion Data |
| fxn | Fast XML Notation Data |
| fxp | Bentley InRoads Survey Preferences Data |
| fxp | Cubase FX Program |
| fxr | Oracle Documaker Font Cross-Reference Data |
| fxs | messiahStudio Scene Data |
| fxt | MakeMusic Finale Script |
| fxtc | Adobe After Effects FXTC Data |
| fxv | SPSD/M FXV Data |
| fxw | eSignal FXW Data |
| fxye | GSAS Data |
| fyc | eSignal FYC Data |
| fyi | Concordance FYI Server Data |
| fyi | FLOWCAL Desktop Data |
| fz2 | JB BAHN Zoom2 Graphics |
| fz4 | JB BAHN Zoom4 Graphics |
| fza | Fattz Announcement Header |
| fza | Form Z Autosave File |
| fzb | Form Z Backup File |
