Guides
Reading a crime rate, one question at a time
Each guide explains one thing about reported crime rates in plain words, with a worked example on a real police agency. The numbers come from the same FBI data as the tools, and every guide says what it does not cover.
- What Does a Crime Rate per 100,000 Mean?A crime rate per 100,000 is reported crimes divided by population, times 100,000. Here is the math on a real police agency, and what the number leaves out.Read →
- How to Compare Crime Rates Between Two CitiesComparing two cities' crime rates takes both sets of inputs, not two bare numbers. A worked example, and why the FBI says not to rank places with its data.Read →
- Why Is 2021 Crime Data Missing for So Many Cities?In 2021 the FBI took crime reports only through its newer system, NIBRS, and thousands of agencies had not switched. What that did to the data, with examples.Read →
- Why Is My State's Crime Rate an Estimate?A state's crime rate is the FBI's estimate, because not every police agency reports. How the gap is filled, how big it gets, and how to read the figure.Read →
- Is Crime Going Up or Down in My City?Whether a city's reported crime rate went up or down is one agency against its own past: two years, two counts, two populations. A worked example, and the 2021 catch.Read →
- What Is the Crime Rate in the United States?The US crime rate is the FBI's estimate of reported crime per 100,000 people. The 2025 figures with the math, why they are an estimate, and what they leave out.Read →
- Which Police Department Covers My Town?A town's crime rate belongs to the police agency that covers it, often the county sheriff. How to find that agency from the FBI's own list, with an example.Read →
- Why Doesn't My Police Department Report Crime to the FBI?Reporting crime to the FBI is voluntary, and since 2021 only possible through NIBRS. The three ways an agency falls short, with two states' counts for 2025.Read →
- How Much Crime Is Reported to Police?Only part of crime is ever reported to police. The Bureau of Justice Statistics' figures on what share reaches police, and what that means for a reported rate.Read →
- Why the FBI's Crime Number Differs From Your Police Department'sA police department's own crime count and the FBI's figure for it often differ. The six reasons, which number CrimeTally shows, and how to use each one.Read →
- How to Calculate a Crime Rate per 100,000Crimes divided by population, times 100,000. The three steps on a real police agency, which population to use, and the mistakes that make a rate wrong.Read →
- What Changed When the FBI Redefined Rape in 2013?In 2013 the FBI widened its definition of rape. See what changed, why state reported crime rates break at that year, and how to read across it.Read →