GTFS Realtime Data (Beta Testing)
Real‑time feeds for Chicago Transit Authority service data — service alerts, trip updates, and vehicle positions — published in the GTFS Realtime format for developers, transit apps, and riders.
Plan & track your trip
Use these CTA tools to see live arrivals and plan your trip across trains and buses.
CTA Train Tracker
See estimated arrival times for 'L' trains at any station across all eight rail lines.
Train Tracker Map
Watch trains move in real time on an interactive map of the entire rail system.
CTA Bus Tracker
Track buses and check live arrival predictions for every CTA bus route.
System Maps
Browse rail and bus system maps, downloadable schedules, and station guides.
GTFS Realtime feeds
These feeds are available in Protocol Buffer (.pb) and JSON formats. An API key is
required — enter yours below and it will be added to each link as ?key=YOUR_KEY.
Enter a key to enable the feed links.
| Feed | Description | Formats |
|---|---|---|
| Service Alerts | Planned work, reroutes, and disruptions affecting CTA service. | .pb .json |
| Trip Updates | Predicted arrival and departure times along each active trip. | .pb .json |
| Vehicle Positions | Current location and status of vehicles in service. | .pb .json |
Need a key? Register through the
CTA Developer Center
to request access to the GTFS Realtime and Train Tracker APIs.