Our Methodology

Data Source

All crime statistics on this site come from the FBI's Uniform Crime Reporting (UCR) Program, administered by the Criminal Justice Information Services (CJIS) division. The UCR Program has been the nation's primary source of crime data since 1930.

Specifically, we use data from the FBI Crime Data Explorer, which provides public access to crime statistics reported by law enforcement agencies across the country.

What We Measure

We track two main categories of crime as defined by the FBI:

Violent Crime

  • Murder and Nonnegligent Manslaughter - willful killing of one person by another
  • Rape - penetration without consent (revised definition, 2013+)
  • Robbery - taking property by force or threat of force
  • Aggravated Assault - attack with a weapon or causing serious injury

Property Crime

  • Burglary - unlawful entry to commit a crime
  • Larceny-Theft - unlawful taking of property without force
  • Motor Vehicle Theft - theft or attempted theft of a motor vehicle
  • Arson - willful burning of property

How Crime Rates Are Calculated

Crime rates are expressed as incidents per 100,000 residents. This normalizes the data across cities of different sizes, allowing fair comparison.

Crime Rate = (Number of Incidents / Population) × 100,000

Safety Score

Our safety score (1-100) provides a quick comparison metric:

70-100 Above average safety (lower crime than national average)
40-69 Average safety (near the national average)
1-39 Below average safety (higher crime than national average)

The score is calculated by comparing a city's total crime rate to the national average. A score of 50 means the city matches the national average.

Known Limitations

  • Reporting gaps: Not all agencies report every year. In 2021, approximately 40% of agencies did not report during the transition from the legacy SRS system to NIBRS.
  • Underreporting: UCR data only reflects crimes reported to and recorded by law enforcement. Actual crime may be higher.
  • Definition changes: The FBI updated its definition of rape in 2013, which affects year-over-year comparisons.
  • City-level only: Data is at the city/agency level, not neighborhood level. Crime rates vary significantly within a city.
  • Data lag: FBI data is typically released 6-12 months after the reporting year.

SRS vs NIBRS

The FBI has transitioned from the Summary Reporting System (SRS) to the National Incident-Based Reporting System (NIBRS):

  • SRS (pre-2021): Agencies submitted monthly aggregate counts of crimes.
  • NIBRS (2021+): Agencies submit detailed incident-level data for each crime.

This transition caused a temporary drop in reporting coverage in 2021. Coverage has since improved, with 94%+ of the US population covered by reporting agencies as of 2023.

Update Schedule

We update our data as the FBI releases new annual statistics, typically in the fall for the previous year's data. The FBI Crime Data Explorer is updated periodically throughout the year.