A/B Street is a transportation planning and traffic simulation software that enables users to model and visualize changes to city infrastructure to prioritize walking, biking, and public transit over private vehicles.
The tool addresses the challenge of communicating urban design alternatives by providing interactive simulation capabilities grounded in real-world data from OpenStreetMap. Users can edit street layouts and intersections, run traffic simulations to observe the effects of their changes, and explore scenarios like low-traffic neighborhoods and 15-minute districts where daily needs are accessible without cars. The approach combines street editing, discrete-event traffic simulation, and intersection geometry modeling to let planners and advocates test infrastructure changes before implementation.
A/B Street suits urban planners, transportation advocates, and community groups seeking to evaluate street redesigns and communicate their impact to stakeholders. The software works anywhere in the world because it draws from OpenStreetMap rather than proprietary data sources. It runs on web browsers, Windows, Mac, Linux, and FreeBSD, lowering barriers to access. The project has evolved into a suite of specialized tools including a cycle network planner, low-traffic neighborhood tool, 15-minute neighborhood explorer, and road prioritization calculator for active travel schemes, allowing users to choose the tool that matches their specific planning task.
The project maintains comprehensive technical documentation covering traffic simulation mechanics and intersection geometry, alongside user guides and developer resources for those building on the codebase. The team actively develops specialized variants addressing distinct planning problems rather than expanding the original tool's scope. The project remains committed to open-source development and reproducible analysis based on public data, with ongoing engagement from contributors exploring how infrastructure changes affect transportation patterns.
