| qwk | QWK Offline Mail Packet |
| qwmod | Intuit Quicken for Windows Module Data |
| qwp | Quiptics Cryptogram |
| qwpx | Quiptics Cryptogram |
| qws | Qt Workspace Data |
| qwz | Question Writer File |
| qxdm | Qualcomm eXtensible Diagnostic Monitor Log |
| qxf | Intuit Quicken Transfer Format File |
| qxf | QPS QINSy Chart Data |
| qxml | Question Master Administration Tool Data |
| qy1 | Cognos Transformer Temporary Data |
| qy2 | Cognos Transformer Temporary Data |
| qy3 | Cognos Transformer Temporary Data |
| qyb | Quantec Yardstick Bank Archive |
| qz | Create A Quiz Data File |
| qza | QIIME 2 Artifacts Data |
| qzb | QuaSZ Zbuffer Data |
| qzd | LS QuizPro Quiz Data |
| qze | LS QuizPro Quiz Data |
| qzp | QF-Test Zipped Split Run Log |
| qzs | LS QuizPro Quiz Data |
| r01 | MicroStation Modification System Resource File |
| r02 | MicroStation Modification System Resource File |
| r03 | MicroStation Modification System Resource File |
| r04 | MicroStation Modification System Resource File |
| r05 | MicroStation Modification System Resource File |
| r06 | MicroStation Modification System Resource File |
| r07 | MicroStation Modification System Resource File |
| r08 | MicroStation Modification System Resource File |
| r09 | MicroStation Modification System Resource File |
| r10 | MicroStation Modification System Resource File |
| r2c | Green Kenue Rectangular Data |
| r2k | Repertoire 2000 Music Database |
| r2lang | Rainlendar v2 Language Data |
| r2lic | Rainlendar v2 License Data |
