Chicago Data Portal FAQ

Introduction

Multiple users of the City of Chicago Data Portal sometimes have the same questions. This page contains some of the most frequent ones and will change and grow over time.

Finding Existing Answers

The best ways to find a question and its answer on this page are either to use the Table of Contents below or to search the page for key words of interest.
Our software vendor also maintains a Knowledge Base that has articles, tutorials, ability to open support tickets, and other resources. Note that the content of that site covers the software features but generally not content specific to Chicago.

City Department Questions

If your question relates to a City business function, such as getting a license, the status of a hearing, or in-depth understanding of the data in a dataset, it often is better to reach out to the relevant department. All departments have pages under the Government tab of the City's main Web site.

Data Not on the Data Portal

If you are looking for data that are not already on the Data Portal, you may want to request it through the Freedom of Information Act (FOIA).

Using the Data Portal

The questions on this page mostly relate to using the Data Portal, itself. If you have such a question and do not find the answer, please feel free to e-mail us.

Table of Contents


Finding Data

How can I find specific records in a dataset?

A common request is to find a particular record or set of records, such as the business license associated with a specific organization. There are multiple ways to do this but the Exploration Canvas feature is a good approach.
From the dataset's Actions menu in the upper right, select Query data.
Query Data Menu
Enter one or more filter conditions and click Apply. When searching for text, such as a business name, unless you are certain how it is entered in the dataset, you may want to use contains or starts with instead of is. Alternatively, use is one of, start typing, and select from the matches presented. Clicking the image below will open the query shown.
Example of Filtering Business Licenses

Using Data On the Data Portal

What do those "computed region" columns in some dataset views mean?

You may see columns like these at the far right of some dataset tables.
Screenshot of computed region columns
The answer for most purposes is that they mean nothing and you should ignore them.
They are values computed automatically by the Data Portal software and are only meaningful within that software, itself. If you want to know a bit more, see here.
While the values in some columns like "Zip Codes" are obviously not valid for Chicago, or valid anywhere in some cases, others like "Community Area" or "Wards" may appear to be the real world values. They are not. Except sometimes by coincidence, these numbers are not the actual values for Community Area, Ward, etc.

Using Data Outside the Data Portal

How can I get a copy of the data in a dataset?

Every dataset has an Export button in the upper right of the page that can be used to download the data in a variety of formats.
This same button also provides a link to the Application Programming Interface (API) for the dataset.

How big will the export of this dataset be?

There is no one answer since a dataset can be exported in a variety of formats. Even for any given format, we do not know without trying the export ourselves. To make a rough estimate, you can create a small, filtered subset of the dataset, export it, and scale up accordingly, based on the number of records in your filtered subset vs. the total number of records in the dataset.

Why can't I download a map as a shapefile or other geographic format, anymore?

For newer geographic (map) datasets, the visual map, such as Boundaries - Wards (2023-) - Map, is not actually the dataset, itself. The dataset is an underlying tabular dataset. As a side effect of that structure, the Export button on the visual map only offers downloads of the table rows but the Export button on the underlying tabular dataset offers shapefile, GeoJSON, and other geographic formats.
The link to the underlying tabular dataset can be a bit obscured in the visual map page. If you do not see it, click More Info towards the top of the page to see the "Based on" link to the tabular dataset.
By the way, eventually all geographic datasets, not just the newer ones, will be in this format.

May I use the data in a dataset for a specific purpose?

Probably. The official Terms of Service are linked from the bottom of the Data Portal home page, this page, and many other pages. However, the whole point of the Data Portal is to provide public data for a wide variety of uses so most normal uses will be fine and are encouraged.

Non-Data Questions

Why was I deactivated as a Transportation Network Provider (rideshare) driver?

While we host TNP data, the Data Portal team plays no role in licensing or other operational issues. Please contact the company that deactivated you and/or the Department of Business Affairs and Consumer Protection.