| qci | Cliq Accessories Phonebook Index |
| qcl | Quark Color Library |
| qcm | 3164 Emulator Quick Command |
| qcn | QPST Content |
| qct | Quick Chart Data |
| qd0 | Omnis Quartz Segment 10 Data |
| qd8 | Omnis Quartz Segment 8 Data |
| qda | KaleidaGraph Data |
| qdat | QuickTime Install Cache |
| qdb | Quicken Data Backup |
| qdd | Rimage QuickDisk Job Data |
| qdf | Quicken Data |
| qdfm | Intuit Quicken for Mac Data File |
| qdfx | Intuit Quicken Financial Exchange File |
| qdi | Quicken Data Index |
| qdt | Intuit Quicken v4 Data File |
| qdw | AnyQuest Questionnaire Definition Data |
| qel | Quicken Electronic Library |
| qem | ExpensAble Report |
| qep | IRMA 3270 Emulation Profile Data |
| qes | Epidata Dataform Definition |
| qf | Diploma Question File |
| qfi | Intuit Quicken 2002 Data |
| qfp | Intuit Quicken Financial Planner Data |
| qft | QF-Test Data |
| qfx | Quicken Financial Exchange Data |
| qgd | Shimadzu GC/MS Data |
| qhf | QIP Saved History Data |
| qhi | Intuit Quicken Home Inventory Data |
| qi | Rsyslog Queue Info |
| qif | Quicken Interchange Format Data |
| qin | CARE-S InfoWorks Inflow Data |
| qix | Intuit Quicken for DOS Index File |
| ql | QEdit Data |
| qld | MassLynx Quantation Data |
