Open Financial Exchange (OFX) is a unified specification that financial institutions can adopt for the exchange of financial data over the Internet.
Created jointly by Intuit, Microsoft, and CheckFree in early 1997, OFX streamlines the work financial institutions need to do to connect to multiple customer interfaces, processors, and systems integrator.
OFX is the language that Quicken and QuickBooks speak to other software applications when they request and receive financial information. When a customer downloads their account data, this data request is encoded in OFX and transparently transmitted over the Internet to an OFX Web server.
The server accesses the customer's account data and returns it to Quicken or QuickBooks in OFX format.