Developer Center

Hello, world!

We’re glad you’re interested in developing applications using data from CTA. This set of data offerings will be able to help you create interesting new applications and mash-ups that’ll help people get the information they want or need about CTA services, wherever they want to receive it.

The information provided through data feeds includes static schedule and service data using an open standard, and APIs that can get you up-to-the-minute information from both CTA Bus Tracker SM and CTA Train Tracker SM. We also have a Customer Alerts API that is a feed of both planned and unplanned events that affect service, as published on transitchicago.com.

What's new

We've published JSON versions of our Train Tracker API, Bus Tracker API and Customer Alerts API endpoints! (Previously, all our feeds were only available in an XML format, only.)

You can find information for each API for how to query for a JSON response in the documentation for each family of APIs.

Send us feedback

We'll continually be working to improve the available tools and content, and we'd love to hear what you think. Drop us a line at webmaster@transitchicago.com.

Terms of use

To use any of CTA’s APIs or data offerings in  your own applications, you’ll need to agree to our Developer License Agreement and Terms of Use. Also, see our CTA Trademarks & You section to help understand what you can and can't do with CTA marks under this agreement.

What’s available

  • CTA Train Tracker API
    Provides up-to-the-minute arrival predictions about trains on the CTA system via the CTA Train Tracker SM service.
  • CTA Bus Tracker API
    Provides up-to-the-minute arrival predictions and location data about buses on the CTA system via the CTA Bus Tracker SM service.
  • Customer Alerts API
    Provides status and detailed information about events (both planned and unplanned) affecting service. This is a gateway into the customer alert database that helps to power transitchicago.com.
  • General Transit Feed Specification (GTFS) Data
    Open format spec used by hundreds of transit agencies to power transit directions in a variety of Web and transit apps, including Google Maps. Many agencies, such as CTA, also share it with the public.
  • Do-It-Yourself Transit Info Display
    This simple Web application makes it easy for you to show CTA bus and train arrival times, plus weather and service alert information, on a screen for all to see—in your lobby, in your shop, in a window... Anywhere that it might help people out!
  • Open Data Sets (KML, CSVs, and more)
    In addition to the feeds hosted in our Developer Center, CTA publishes data sets via the City of Chicago's data portal. Many of these sets (which include ridership reports, mapping shapefiles, and more) could prove useful in your projects.
  • RSS Feeds
    Simple feeds of information on service and news from CTA, as it becomes available on our Web site.

More information

Our styles and branding

We have a carefully considered and implemented set of design and brand standards and styles we use to establish a consistent, reliable and clear brand identity for us and with which our riders engage. You're welcome to reference official route colors in your designs and use certain icons, but not CTA trademarks except in specific ways that are permitted. To help you better understand what is and isn't okay to do, we've created this page to provide guidance and some detailed instructions (including icon downloads):

CTA Trademarks & You

While we provide the data and maintain the sources, we’re not able to provide support directly in how to write your software. We do, however, provide some pointers and tips to help get you started. There are also some helpful resources on other websites, which we're happy to point you to.

Further reading and help

System status snapshot
‘L’ route status
Red Line
Normal Service
Brown Line
Normal Service
Green Line
Normal Service
Orange Line
Normal Service
Pink Line
Normal Service
Purple Line
Normal Service
Yellow Line
Normal Service
Bus routes w/alerts
Elevator alerts