Industry Foundation Classes (IFC) is a standard, open data model used in the construction industry. Defines the characteristics of data related to the design, construction, maintenance and operation of civil works.

The IFC specification is open and publicly available.[1] Version IFC4 is an international ISO standard, published as ISO 16739, "Industry Foundation Classes (IFC) for data sharing in the construction and facility management industries".

The development of IFC dates back to 1994, when Autodesk promoted the formation of a consortium to build a set of classes (defined in the C++ language) that would standardize the development of software applications. The consortium included AT&T, HOK Architects, Honeywell, Carrier, Tishman and Butler Manufacturing.[2] and initially took the name Industry Alliance for Interoperability.

Based on the work of said consortium - which later became a non-profit organization - the bases were established for the definition of the Fundamental Classes for the Architecture, Engineering and Construction Industry (AEC), trying to cover the life cycle of the projects. In 2005 the alliance changed its name again to adopt buildingSMART.

IFC-XML format files are 4 to 8 times larger than the corresponding IFC-SPF files.[3]​.