IFC is the open BIM (Building Information Modeling) interchange standard maintained by buildingSMART. Used by every major AEC software, Revit, ArchiCAD, AutoCAD, Tekla, Bentley, to exchange architectural and structural model data. The format is text-based STEP (ISO 10303), verbose but human-readable. The current spec is IFC 4.3 (released 2024).
How to open
Revit, ArchiCAD, AutoCAD, Tekla, Bentley OpenBuildings. Free viewers: BIMcollab Zoom, IFC++, BIMVision, Solibri Anywhere.