There is only one file type that uses the .OFX extension:
Open Financial Exchange File
An OFX file is a financial data file created in the Open Financial Exchange (OFX) format, an open format for transferring data between vendors, consumers, and financial systems. It contains transactions, statements, and other financial information. OFX files are typically sent to individual users as credit card or banking statements from a financial institution.
OFX is an SGML-based file format standardized in 1997 by Intuit, Microsoft, and CheckFree. It replaced the Open Financial Connectivity (.OFC) format used by Microsoft Money and is now the standard container for financial information under the Open Financial Exchange Consortium.
Updated: September 17, 2019