About the Data

CrimeAtlasUSA is built from the FBI Crime Data Explorer (the Uniform Crime Reporting program and its transition to NIBRS) and U.S. Census Bureau population figures, which we use to express counts as a rate per 100,000 residents.

Reported crime, not all crime

These figures count offenses that were reported to police and then submitted by the police agency to the FBI. Crimes that were never reported, and agencies that did not submit data, are not in the count. A change in a number can reflect a change in reporting as much as a change in crime.

Why we show coverage on every page

The FBI collects data from about 19,000 law-enforcement agencies, and in any given year some do not report or report partially. We show how many agencies covering an area submitted data. Where coverage is low, the rate is unreliable and we say so; we do not compare two places with very different coverage without flagging it.

Cities and police agencies

The FBI reports by police agency, not by city. One city can be served by several agencies, and one agency can cover several communities. We map agencies to places with a confidence level, and a place that can't be matched with enough confidence does not get a page.

Language we avoid

We never write that a place is "safe" or "dangerous", and we do not publish "most dangerous cities" lists. Statements are of the form: "the reported violent crime rate was X per 100,000 in 2024, based on data from Y of Z agencies." We do not publish neighbourhood-level figures, where the error is too large to be meaningful.