| q3x | QuickDraw 3D Extension |
| q43 | Aqbanking Q43 Data |
| q4w | Qualitek-4 Exported Data |
| qa | GPS Quality Assessment Data |
| qaa | WinQSB Data File |
| qag | Norton Desktop Quick Access Group Data |
| qam | Omnis Quartz Audio |
| qar | QlikView Extension |
| qat | Microsoft Office Quick Access Toolbar Data |
| qb | Diploma Question Bank File |
| qb | Qubicle Binary Data |
| qb2005 | QuickBooks 2005 |
| qb2006 | QuickBooks 2006 |
| qb2007 | QuickBooks 2007 |
| qb2009 | QuickBooks 2009 |
| qb2010 | QuickBooks 2010 |
| qb2011 | QuickBooks 2011 |
| qb2012 | QuickBooks 2012 |
| qbd | SQL Navigator Query Builder Data |
| qbi | Intuit QuickBooks Image file |
| qbk | Intuit QuickTax 2009 Backup |
| qbl | Intuit QuickBooks License File |
| qbmb | QuickBooks Backup |
| qbmd | QuickBooks Backup |
| qbo | Intuit QuickBooks Online Bank Statement |
| qbp | Intuit QuickBooks Print File |
| qbquery | MySQL Query Browser Saved SQL Query |
| qbs | Navicat for MySQL Query Builder Tables Data |
| qbt | Intuit QuickBooks Temporary File |
| qbt | Qubicle Binary Tree Data |
