Closed O/D and Segment Flow APIs Overview
The Origin/Destination APIs provide use-case-driven tools for analyzing journey flows between defined zones, with simplified parameters and faster processing compared to the legacy O/D API.
API background
The Closed Origin/Destination and Segment Flow APIs are purpose-built analytical tools, each designed around a specific journey flow question. This focused design enables:
- Simplified parameters
- Faster processing (target magnitude: 50% reduction)
As each API targets one analytical question, outputs are consistent and predictable regardless of which zones or corridors are included in a query.
API comparison
Use the following table to identify which Origin/Destination API matches your analytical question.
Journey counts between the Closed O/D and Segment Flow OD APIs are not directly comparable. The APIs measure fundamentally different units: Closed O/D counts pairwise zone journeys; Segment Flow OD counts flow-based traversals of a corridor.
API | Question | Attribution method | Best suited for |
|---|---|---|---|
How much freight moved from Zone A to Zone B? | Pairwise attribution: journey count is stable regardless of query scope | Trip demand, freight flows, and stable zone-to-zone baselines | |
How much traffic used this corridor? | Passthrough attribution: counts run 10% to 20% higher than Closed O/D | Highway utilization, toll revenue, corridor siting, and EV charging infrastructure | |
What are my general O/D flows? | On-the-fly: count varies based on zones included in the query | Migration to Closed O/D or Segment Flow O/D |
