File extensions start with character 'Q'
| File Type | Category | File Format | |
|---|---|---|---|
| .q07 | Data Files | QuickTax 2007 Tax Return | |
| .q08 | Data Files | QuickTax 2008 Tax Return | |
| .q09 | Data Files | QuickTax 2009 Tax Return | |
| .q3d | Data Files | Quest3D Project File | |
| .qb2005 | Data Files | QuickBooks 2005 File | |
| .qb2006 | Data Files | QuickBooks 2006 File | |
| .qb2007 | Data Files | QuickBooks 2007 File | |
| .qb2009 | Data Files | QuickBooks 2009 File | |
| .qb2010 | Data Files | QuickBooks 2010 File | |
| .qb2011 | Data Files | QuickBooks 2011 File | |
| .qb2012 | Data Files | QuickBooks 2012 File | |
| .qbmb | Backup Files | QuickBooks Backup File | |
| .qbw | Data Files | QuickBooks Data File | |
| .qda | Compressed Files | Quadruple D Archive | |
| .qdat | Data Files | QuickTime Install Cache File | |
| .qdf | Quicken Files | Quicken Data File | |
| .qdfm | Data Files | Quicken Data File (Macintosh) | |
| .qdl | Text Files | QDL Program | |
| .qel | Data Files | Quicken Electronic Library | |
| .qf | Quicken Files | Qompose Web Page Template | |
| .qfx | Data Files | Quicken Financial Exchange File | |
| .qic | Backup Files | Windows Backup File | |
| .qif | Data Files | Quicken Interchange Format File | |
| .qlgenerator | Apple Files | Quick Look Generator File | |
| .qm | Data Files | Qt Compiled Translation Source File | |
| .qmg | Raster Graphics Files | Samsung Theme Graphics File | |
| .qpb | Data Files | QuickBooks Point of Sale Data File | |
| .qpf | Data Files | Quartus II Project File | |
| .qph | Data Files | Quicken Price History File | |
| .qpm | CAD Files | Quick Pallet Maker Input Data | |
| .qrc | Configuration Files | Qt Resource Collection File | |
| .qrp | Data Files | QuickReport File | |
| .qsd | Data Files | Quicken Data File | |
| .qtch | Digital Video Files | QuickTime Cache File | |
| .qtz | Digital Video Files | Quartz Composer File | |
| .qvd | Data Files | QlikView Data File | |
| .qvp | Data Files | ViewletBuilder Project File | |
| .qvt | Configuration Files | QlikView Theme File | |
| .qvw | Data Files | QlikView Document | |
| .qxf | Quicken Files | Quicken Essentials for Mac Exchange File |