QIF to IIF Converter that will let you automatically convert a Quicken file (QIF) to the QuickBooks format (IIF). Simple two click process and your data is imported into Quickbooks! The Internet banking that is provided by lots of the online banks exports in QIF. If you use QuickBooks, you need to convert the Quicken QIF file to an IIF to be able to read it in Quickbooks. The program supports credit card transactions as well as checks.