| fq | FASTQ Sequence |
| fqf | FlashFXP Queue Data |
| fqm | Mental Ray Renderer Result Data |
| fqy | FLAMES Command File |
| fr | STK Frequency Information File |
| fr3 | Fractal Explorer 3D Attractor |
| fr3d | FaceGen 3D Model |
| fr4 | Fractal Explorer Quaternion Spot |
| fra | Fractal Explorer Animation |
| fra | Adobe Acrobat Reader French Language Data |
| frac | Tinker Fractional Coordinates |
| fract | Free Form Fractional Chemical Data |
| frag | SAM A2M Alignment Data |
| fragment | IBM DB2 Fragment Data |
| fram | Adobe FrameMaker Interchange Format Data |
| frame | Adobe FrameMaker Interchange Format Data |
| frames | xScope Frames File |
| frb | Microsoft FRx DrillDown Viewer Report Book |
| frd | Frequency Response Data |
| frd | Mandelbrot Explorer Fractal Definition File |
| frd | Microsoft FRx DrillDown Viewer Enhanced XML |
| frdat | Abbyy FineReader Data |
| frec | Fiasco Database Frequencies File |
| fred | Flight Recorder Electronic Documentation Data |
| freepp | Free PDF Perfect Data |
| freq | SAM Frequency Model Data |
| fres | Autodesk Inventor Stress Analysis Results Data |
| frf | Abbyy FineReader Intenal Page Data |
| fri | Fractal Explorer IFS Spot |
| frk | FORMIK Data |
