OpenTripPlanner

OpenTripPlanner (OTP) is an open-source multimodal passenger routing and accessibility analysis engine. It consumes standard General Transit Feed Specification (GTFS and GTFS-Realtime) transit data together with OpenStreetMap (OSM) pedestrian, cycling, and road networks to compute realistic journey trajectories across buses, trains, metros, walking, and shared mobility.

Urban planners, transport researchers, and civic advocacy groups use OTP to model public transit accessibility, measure transit equity across lower-income neighbourhoods, and evaluate the impact of proposed transit route changes or bus frequency adjustments.