UrbanSim

UrbanSim is an open-source software platform for urban simulation used to support land-use and transportation planning. It facilitates integrated modeling of where people live and work, how they travel, and how urban form evolves over time under different policy scenarios.

Built on an agent-based, microsimulation approach, UrbanSim represents households and jobs as agents that make location and travel decisions based on economic and behavioral models. The platform links land-use development with travel demand, enabling users to test policies such as zoning changes, housing supply adjustments, or transit investments and observe effects on housing affordability, job access, traffic, and emissions.

UrbanSim relies on a flexible data model including entities such as parcels, buildings, households, and employment. It supports scenario comparison, calibration against observed data, and integration with geographic information systems and external models. Outputs typically include forecasts of population and employment distribution, land use mix, travel patterns, and key indicators like accessibility and congestion.

The project is developed and maintained by an international community of researchers and planning practitioners. It is designed as an extensible framework that can be customized with analytical modules and data sources, and it is widely used by government agencies, universities, and consulting organizations for long-range planning and policy analysis.