Crime in Chicago
An interactive analysis of crime in Chicago's 50 wards (beta)


What is this?

Crime in Chicago is a data visualization by Open City that lets you explore crime trends in Chicago's 50 wards. It was built using open data about Chicago crimes released by the Chicago Police Department.

With this website, you can compare crime levels over the years and across city wards. You can further explore each ward’s crime profile, which shows daily crime volumes going back to 2002, crime types and subcategories, and contact info for each Ward Alderman.

How does it work?

  1. First, pick a year and a ward on the home page. If you don’t know what ward you’re in, enter in your address to find it. Wards with more crime have higher bars. about/ward-selector.png

    The ward selector

  2. This will bring up a heatmap that displays an entire calendar year of crime for that ward. Each square represents a day. The darker the square, the more crimes occurred that day. about/ward-42.png

    A year of crime in Ward 42 by volume

  3. To compare wards, choose multiple wards from the 'Select wards' section. You can stack two different ward heatmaps, or view multiple years of crime for a single ward.
  4. Once you have a ward selected, click on its name to view that ward's crime trends. You can discover how crime in the ward has changed over time, what crimes occur most frequently, and how crime activity fluctuates across the day. about/ward-42-expanded.png

    Expanded details for Ward 42

  5. To view a ward’s crime profile, click on the “View all ward details” link. This will bring you to a detail page featuring heatmaps of the past 10 years of crime in the ward, contact info for each alderman, and a breakdown of all these crimes by category.


    Crime types

    On the right, you can see the minimum (low), average, maximum (high) and total number of crimes in each category. Click on each crime category to see the legal definition of the crime, a closeup of the chart showing the number of times that crime has occurred per month, and a table containing subcategories of that crime type.

    These subcategories come from the Chicago Police Department. Fair warning: they can be a little messy and cryptic.

Who is it for?

This free tool is for anyone interested in crime in Chicago. It was designed to be simple and to allow anyone to visualize crime trends in their community.

It can be used by:

Why did you build it?

A few reasons:

Why offer a poster?

We've never done one before, and we thought that crime for all 50 wards would be a great dataset to make a static visualization of. Get one now!

All of the proceeds for the poster will go towards hosting for this site and continued development on projects for Open City.

Why is this site in 'beta'?

This site is currently a work in progress. We have a lot of ideas on features that could be added, but wanted to release something as soon as we could that would be genuinely useful to people. With time, and your feedback, we hope to graduate this app out of beta soon!

Why are you showing crimes by ward?

There are many useful ways to group crime geographically: by neighborhood, police district, community area and many others. Wards were a good first step and proof of concept.

Where does this data come from?

The Chicago Police Department has tracked crime incidents in the city for years, but they have never before released this data to the public.

In September 2011, the CPD released anonymized records of the 4,802,684 reported crimes that took place in Chicago from 2001 to 2011. This data is now available on the City of Chicago's data portal. It is updated daily.

Anything I should know about this data?

Who built Crime in Chicago?

This site was built by Open City, a volunteer group of technologists and researchers based in Chicago that create civic apps with open government data.

Team members:

Check out our other projects, and feel free to get in touch at

Can I get this site for my city?

Want to deploy this app in another city? All the code is up on github.

What technologies did you use to build the site? (For the Geeks)

Report a bug

If you notice a bug on this site, or something doesn't quite work as you expect, please contact us at

About this site

Crime in Chicago is a data visualization by Open City that lets you explore crime trends in Chicago's 50 wards. It was built using open data about Chicago crimes released by the Chicago Police Department.

More about this project »


Get the poster

See crime data for all 50 wards compared on a single poster printed on high-quality materials.

Pricing and details »