Publishing data for the world to use

An important step in releasing open data is determining how it will be made available. To some extent, this decision will be a function of what kind of data you want to release and the format it is currently in (i.e., how it is used or maintained internally)

One of the most common types of city data is geospatial data, or data that relates to a specific place. This may be things like the locations of points of service, like a library or police station, or of physical assets like fire hydrants or street lights. It is common for city data to have a geospatial component - the location of a crime, or a pothole that is reported to 311.

The easiest and most efficient way to make geospatial data available to outside consumers is to work through the GIS Services Group within OIT - they can best advise your department on the proper approach for releasing geospatial data.

OIT has developed an ArcGIS Desktop Python toolbox that makes exporting ArcGIS feature classes to open geodata formats (GeoJSON, KML, CSV and shapefile, compressed and uncompressed) very simple and straightforward. Information on how to install and use this tool can be found here.

If your department’s data changes somewhat infrequently, or will be accessed only periodically it may be appropriate to release such data as a static download in a commonly used format (e.g., comma separated value). However, if your data is updated frequently or subject to changes - or if it will be targeted for specific user communities like software developers - it may make sense to consider provisioning an Application Programming Interface (API) for your data.

The Chief Data Officer and the Web and Data Services Team at OIT can best advise your department on the feasibility of using an API for your data, the tradeoffs of using an API over static downloads and the pros and cons of different API platforms and frameworks. is a data directory - think of it as a "white pages for data." It makes your data more discoverable and easy to find for those that may be interested in using it. This site is well known in the Philadelphia technology and data communities and also contains data from a variety of different data producers from around the region.

Once your data is staged for use by consumers - whether it is a static downloadable data set or an API - contact the Chief Data Officer with the details of your release to get an entry added to

The listing for your data in will be used to communicate it’s availability to data consumers and other interested parties in Philadelphia and beyond.


PHLAPI is a City of Philadelphia website that provides detailed information on open data made available through Application Programming Interfaces (APIs). This site is geared toward software developers and others that are typically more advanced and experienced data users. The audience that this website serves is much more narrowly focused than, and data listings on this site included detailed API documentation, code samples and helper libraries.

If your data is available through a publicly accessible API, contact the Chief Data Officer to create a new entry on the PHLAPI site.


GitHub is a platform that is used primarily for sharing the code that makes up software solutions. However, in response to a number of important improvements being made to the GitHub platform, we are using it as an important part of our open data program - more and more of our open data is being released on GitHub because of the many benefits it provides.

The City maintains a GitHub organization that is available to any city department or agency for releasing new data sets. To be added to the City’s organization, and to obtain access to repositories for adding new (or enhancing old) data sets, contact the Chief Data Officer.