| Abbreviation | Definition |
|---|---|
| QD3 | QuickDraw 3D Metafile (QuickDraw) |
| QD3D | QuickDraw 3D Metafile (QuickDraw) |
| QD4 | Omnis Quart Data file - segment 4 |
| QD5 | Data file - segment 5 (Omnis Quartz) |
| QD6 | Data file - segment 6 (Omnis Quartz) |
| QD7 | Data file - segment 7 (Omnis Quartz) |
| QD8 | Data file - segment 8 (Omnis Quartz) |
| QD9 | Data file - segment 9 (Omnis Quartz) |
| QDF | Quicken Data File |
| QDK | Backup of startup files created by Optimize (QEMM) |
| QDV | Bitmap graphics (8bit) (Random Dot QDV file) |
| QDV | Quark Xpress Dictionary File |
| QDX | QDX Compression Format |
| QEF | Query file (Q+E for MS Excel) |
| QFC | Compressed file archive |
| QFO | QuakeForge files |
| QFX | Fax (QuickLink) |
| QHF | Queue Header File |
| QIC | Quarter Inch Cartridge Backup set ( Microsoft Backup) |
| QIF | Quicken Interchange Format |