Embodiments relate to systems and methods for object-based modeling using hierarchical model objects. A modeling client can host modeling logic and an application programming interface (API) to create, access, manipulate, and import/export modeling objects used in modeling applications, such as engineering, medical, financial, and other modeling platforms. In aspects, the source data accepted into the modeling client can include consumer or business-level applications, whose spreadsheet, database or other content can be extracted and encapsulated in extensible markup language (XML) or other object-oriented format. Various model objects can be extracted from source data, and aggregated into a hierarchical model object encapsulating and preserving the underlying object layers. In aspects, one or more of the model object layers can functionally combine at least two other layers, to relate levels of data in hierarchical fashion. The modeling client can exchange composite or other modeling objects with external platforms on a programmatic basis.