By weighing factors that affect parking use at multi-family housing sites, the calculator helps users consider how much parking is “just enough” when making regulatory and community decisions about development.

The calculator produces parking use estimates in the context of a specific site, based on a model using current local data of actual parking use correlated with factors related to the building and its surroundings.

The calculator’s estimates are based on a model developed from extensive field work on data collected mostly in the fall of 2014 and spring of 2015 on over more than 90 multi-family buildings across the District.