How we count

Every number on this site comes from City of Chicago open data files. This page explains, in plain words, how we turn those files into counts. The complete rules, with the City's crime codes, are in our full counting rules (plain text).

Last updated Oct 11, 2026.

People, not cases

Our default count is people. If one shooting hits four people, that is four people shot. The CPD-style option counts each shooting case once instead, and leaves out justifiable and involuntary homicides. It is our approximation from open data, not the official CPD number.

Shootings and homicides

People shot means people wounded or killed by gunfire, from the City's victim-level file. Homicides (all causes) means everyone killed by another person, by any means, so it includes deaths that were not shootings. That is why the homicide column does not add up with the shooting columns. Suicides are not counted.

Assaults

Assault reports are the CPD Assault category in the City's Crimes file: simple and aggravated assault (threats and attempts). Battery is a separate category and is not included. Sexual assault is CPD's Criminal Sexual Assault category only. These are reported incidents, not people.

Dates

We use Chicago time and when an incident happened, not when it was reported. Each file's newest day is usually still filling, so year-to-date and 4-week numbers stop at the last complete day, the day before. In early January, when the year has less than two weeks of data, we compare the last 4 weeks instead. Date ranges, including the map's From and To, include both end days.

Weekly and weekend briefs

A week runs Monday to Sunday. A weekend runs Friday noon to Monday 6 a.m. A number marked partial covers a period the City's files do not fully reach yet; pending means too little is loaded to show a number.

Neighborhoods

We use Chicago's 77 official community areas. Rates are per 100,000 residents, using 2020 Census populations. Small areas can swing a lot, so changes on small numbers show the counts first (“5, up from 1”).

The Victims page

Shootings there are daily, like the rest of the site. Other crime types come from the City's quarterly victim file, so they cover finished quarters only. The City hides groups of fewer than 3 victims, so breakdowns can add up to a little less than totals, and some victims have no published age. Race is the CPD race code; there is no separate ethnicity field. Traffic deaths and serious injuries are shown separately and never added to crime counts.

The CTA page

The CTA page counts crime reports, not people: every CPD Crimes row whose location is a CTA station, platform, train, bus or bus stop. Its default view is violent crime including simple battery(homicide, criminal sexual assault, robbery, aggravated assault and all battery), which the rest of the site does not count; toggles add theft, other property crime, narcotics and weapons, and everything else.

  • Each rail report goes to the nearest “L” station within 150 m. Stations in the Loop are close together, so a report can land on a neighbor. Transfer stations count reports from every line serving them. Reports farther than 150 m from any station are in the rail total but not on a station.
  • Crimes on a moving train are logged where they were reported or where police met the train, often a later or bigger station, not where they happened.
  • Bus routes are not in the CPD file. A bus report is shared among every route within 50 m, weighted by each route's ridership.
  • Rates use the CTA's station entries (5neh-572f) and bus rides by route (jyb9-n7fm) for the same days as the crimes: each published month counts its total divided by its days, for each day of the window that falls in it. The CTA publishes ridership a few months behind the crime data, so days after the latest published month use that station's or route's average daily ridership over the latest 12 published months; rates that include such days are marked “est.”. Entries count people entering a station, not exits or transfers, so they undercount riders; bus rides count every boarding, so rail and bus rates are not like-for-like. Stations under 500,000 entries a year swing a lot; the 1M-entries and 2M-rides cutoffs for the rate tables are per year, scaled to the window's length.
  • Stations outside Chicago (Evanston, Skokie, Oak Park, Forest Park, Cicero, Rosemont) are greyed out: CPD does not cover them, and their entries are left out of rates.
  • Locations are block-level. The Crimes file runs about a week behind and is revised; the window stops the day before its newest day. The page keeps two years of reports, so any window in the last 12 months can be compared with the same dates a year earlier (Feb 29 maps to Feb 28).

Revisions

The City's files are preliminary. Rows are added and corrected, and crimes that are not reported never appear. We re-read the files every night, so past numbers can change a little.

Sources

Arrestee race on shooting cases

Counts are arrest rows (CPD arrests file, dpt3-jri9) whose case_number matches a shooting-victim case from this year, through the last complete day. They are not proven shooters, and the arrests file has no age or sex. 156 of 1,255 shooting cases have at least 1 arrest row (171 arrest rows).

An arrest is not a conviction and often is not the person who fired. Many shootings have no arrest, and one case can have several. Do not read this as who shot whom.

  • Black / African American126 · 74%
  • White Hispanic36 · 21%
  • White5 · 2.9%
  • Asian / Pacific Islander3 · 1.8%
  • Black Hispanic1 · 0.6%

Changelog

  • 2026-10-11: CTA page (violent crime by "L" station, Red Line and bus route, with crime-type toggles) and the CTA section above.
  • 2026-10-10: The map opens on people shot through the last complete day, and map date ranges include the To day. Area pages list shootings first. This page rewritten in plain language; the full rules moved to /api/definitions.
  • 2026-10-10: Victims page (quarterly victim file, places, traffic) replaced Who's hit.
  • 2026-10-09: One last-complete-day for every year-to-date number; early-January rule; Trends page.
  • 2026-09-19: People shot counted from the City's victim-level file; names never stored.