QIF stands for Quicken Interchange Format. Was introduced by Quicken a long time as a way to transfer financial data between other software and Quicken, between bank downloads and Quicken, and is still very useful.
The QIF file format is supported by various financial applications (some of them listed below):
Quicken itself (all Windows versions up to the latest 2017 and Quicken for Mac 2007 (including Lion edition). Quicken stopped “officially” supporting its invented format in 2005, but it fully supports in the application if QIF files are prepared correctly in “Quicken” flavor. The Transactions app, CSV2QIF, PDF2QIF, FixMyQIF, QBO2QIF, Bank2QIF, OFX2QIF and others all capable of creating fully importable QIF files for all account types. Quicken also exports files in this format as the only option available to get your data out of Quicken (this does not apply to Quicken Essentials for Mac).
YNAB (you need a budget) – full throttle personal finance tool.
Simple Home Budget - Simpler and more affordable personal finance tool.
iBank/Banktivity (for Mac) – a great alternative to Quicken
Simple – this plain text file format easy to create and edit either by software tools or manually by a text editor
Comprehensive - Covers most user needs to record transactions including split transactions, bank reconciliation, investment transactions, categories, and tags. Other financial formats often missed one or more QIF features
Structured - QIF supplies data in the expected form. Unlike CSV as a generic format, either software or user can read and understand the data in the QIF file
QIF and QFX are plain text formats (can be opened and edited with a text editor), but QXF is an encrypted container
QIF supports split transactions, categories, tags, address when QFX does not have these features
QIF is the simplest between these three formats, and the most widely supported
This article explains why Quicken moves from QIF to QFX (OFX). However, QIF is still widely supported, including all Quicken versions (for Windows, and Quicken for Mac 2007 recently updated to support OS X Lion).
Another issue is that you cannot use the Quicken Interchange file ‘directly,’ even if you can open and see it in the text editor. Use QIF2CSV to convert QIF files to CSV format compatible with Excel and other spreadsheet software.
Since the format was widely used, there are several variations presenting data in a different way which can cause incompatibility across different software packages or when used in different countries:
order of attributes to describe transactions
If you are using Quicken right now, you can rely on QIF format as your ability to import your transactions into Quicken. The Quicken Interchange file you are importing has to follow certain rules to make Quicken or other software import it. ProperSoft tools should help you with this task.
Since the format is so simple and has many features, most likely will be widely used as a move transactional data. Many mobile apps created lately to support the format for import, export, and exchange.