The Building Performance Database (BPD) is the nation’s largest dataset of information about the energy-related characteristics of commercial and residential buildings. The BPD combines, cleanses and anonymizes data collected by Federal, State and local governments, utilities, energy efficiency programs, building owners and private companies, and makes it available to the public. The web site allows users to explore the data across real estate sectors and regions, and compare various physical and operational characteristics to gain a better understanding of market conditions and trends in energy performance. Using the Application Programming Interface (API), users can query the same analytical tools available through the web interface. The API enables the sharing of content and data between applications, meaning that third party web or mobile applications can be dynamically updated with BPD data.a