FAQ

Updated December 27, 2010

What is the format of this feed?

WMATA data is accessible in real-time via webservices that support Representational State Transfer (REST), JavaScript Object Notation (JSON/JSONP).

Does Metro charge for this service?

No.

Does Metro allow for profit applications that use this data?

Yes, any developers (including for-profit developers) are welcome to use the webservices in any way that they see fit as long as they conform to the Terms of Use. 

Other than agreeing to a license, do developers need accounts/API keys or other mechanisms?

Developers need to register and get an API key.  Metro is using Mashery as a front-end to handle registration, API key distribution and general management of the data flow.

What sort of load are Metro's servers able to handle?

Metro is employing cloud computing for this effort – there is no impact on Metro’s infrastructure. 

Are there limits on the amount of data any single application or developer is able to use?

Metro has the ability through Mashery to control and meter traffic associated with an individual API key. The current default setting for developers is no more than five calls per second and ten thousand calls per day.  The ceiling can be raised for either a specific API key or globally if needed – we expect to make adjustments to the default settings over time.  Our goal is to encourage the development of applications that our riders will be excited about.  We do not want to introduce any limitations that would work counter to that goal.  

I am ready to deploy my application.  How can I get my data limits increased?

When you are ready to release your app please contact Bill at wrigney@wmata.com to discuss an appropriate rate increase.  He will work with you to determine an appropriate rate that will ensure a smooth launch for your app.

How real-time is "real-time"? Is the data updated continuously or is there some sort of delay?

It will vary based on the type of information requested and the system that it is drawn from. Our goal is to provide the data as close to “real-time” as possible.  

What sort of applications does Metro expect/hope developers will make?

On the one hand we would be delighted to be surprised with applications that are totally unexpected.  On the other hand we anticipate encouraging the developer community to develop apps to help us solve three Metro problems: 1.) getting our riders better information in real time, when and where they need it; 2.) making our real time information more accessible and useful for our customers with disabilities and 3.) offering better regional, multi-modal transportation information. 

Why has Metro chosen to do this now?

Metro has made a series of successful investments over the past three years that have improved our ability to deliver high quality information in real time.  Our internal Service Oriented Architecture (SOA) has greatly increased our ability to draw data from disparate systems throughout the enterprise.  Re-factoring some of these web services for benefit of developers and our customers was a logical next step.