Chile Safety Map
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Methodology — How We Calculate Crime Rates

This page explains in full how we collect, process, and present the crime statistics on this site: the source of the data, the rate calculation, the underreporting caveat, how we define trend directions, the criteria we use for comparisons, and — critically — what these figures cannot tell you. We use the first-person "we" to refer to the ischilesafe.com editorial team throughout.

Data source: CEAD

All quantitative crime data on this site comes from CEAD — Centro de Estudios y Análisis del Delito, the Chilean government's official crime statistics body, which operates under the Ministerio del Interior y Seguridad Pública.

CEAD compiles police-recorded incident data from two law enforcement agencies:

  • Carabineros de Chile — the uniformed national police force, which handles the majority of recorded incidents.
  • Policía de Investigaciones (PDI) — the plainclothes investigative police, which handles more complex criminal cases.

CEAD publishes annual series from 2005 onward at the commune, regional, and national level. We access this data via CEAD's official public endpoints (cead.ministeriointerior.gob.cl). The raw data is processed by our open-source pipeline, validated against a strict schema, and stored as versioned JSON files in the project's public GitHub repository. The full scraper and validation code is available for inspection.

We use only the annual series (serie anual) and only the total-case measure (casos policiales — both formal complaints and arrests). We do not use quarterly or monthly figures. We include data up to and including the latest complete year published by CEAD; partial years (where CEAD has not yet closed the annual series) are excluded from rates and rankings to avoid comparisons against incomplete periods.

Map boundaries: chilemapas

The commune boundary polygons displayed on the interactive map are sourced from chilemapas (github.com/pachadotdev/chilemapas / pacha.dev/chilemapas), a project by Mauricio Vargas Sepúlveda licensed under the GNU General Public License v3 (GPL-3). The chilemapas boundaries are derived from official Chilean government sources: INE (Instituto Nacional de Estadísticas), SUBDERE (Subsecretaría de Desarrollo Regional y Administrativo), and BCN (Biblioteca del Congreso Nacional de Chile).

The map geometry (commune shapes) comes from chilemapas; the crime statistics overlaid on those shapes come from CEAD (described above). These are separate, independent sources.

How the rate is calculated

The primary metric on this site is the rate per 100,000 inhabitants. We use the rate as published directly by CEAD (medida = tasa por 100.000 habitantes), which applies INE (Instituto Nacional de Estadísticas) population projections as the denominator for each commune, region, and national aggregate.

Using CEAD's own published rate — rather than computing our own from raw counts and INE population figures — ensures consistency with the official source cited on every page.

Important note on national and regional figures: The national and regional totals that CEAD publishes as tasa por 100.000 are sum totals — that is, the sum of all commune rates in the territory, not a weighted per-capita average. We do not display these sum figures as averages. When we show a national average for comparison purposes (e.g., on commune pages and the lowest-reported-incidence ranking), we compute the unweighted mean of non-low-population commune rates using each commune's individual rate at its latest complete year. This is the correct per-capita comparative figure.

Communes with populations below 10,000 inhabitants are excluded from national and regional averages and from the lowest-reported-incidence ranking. Small populations produce highly volatile per-capita rates because a single incident can produce a large per-100k figure. Their individual commune pages still display the rate with a volatility caveat.

Underreporting (cifra negra)

All figures on this site represent police-reported incidents only. They do not represent the total number of crimes committed. The gap between actual crime occurrence and reported crime is called the cifra negra (literally "dark figure") or underreporting rate.

Underreporting is not uniform across crime types or localities. Key patterns documented in Chilean crime surveys (Encuesta Nacional Urbana de Seguridad Ciudadana — ENUSC):

  • Property crime (theft, robbery) has relatively high reporting rates when insurance or bureaucratic requirements (e.g., police reports for insurance claims) incentivise victims to file. But opportunistic petty theft is widely underreported.
  • Intra-family violence is significantly underreported across all socioeconomic groups. Survey-based prevalence estimates are consistently higher than police-recorded figures.
  • Homicides have the lowest cifra negra of any crime category because deaths are discovered and recorded regardless of victim reporting. Homicide rates are therefore the most reliable indicator in CEAD data for inter-commune and inter-year comparisons.

A commune showing a low reported rate may have low actual crime prevalence, high underreporting, or both. We cannot determine the proportion from police data alone. Where appropriate, individual commune pages note these caveats.

Trend formula

Each commune page and map pin displays a trend indicator: rising, falling, or stable. We compute the trend as follows:

  1. Take the latest complete year rate (year N) and the rate three years prior (year N−3), both from the CEAD annual series.
  2. Compute the percentage change: ((rate_N − rate_N3) / rate_N3) × 100.
  3. Apply a 5 % threshold: if the change is more than +5 %, the trend is rising; if less than −5 %, it is falling; if within ±5 %, it is stable.

We use a three-year window rather than a single year-over-year comparison to reduce the influence of anomalous single-year fluctuations (e.g., pandemic-era reporting disruptions). If a commune has fewer than four complete years of data, the trend is not computed and is omitted from display.

The 5 % threshold was chosen to avoid labelling statistically marginal changes as meaningful trends in communes with small absolute case counts. For communes with large populations and stable series, the threshold provides a conservative signal; for smaller communes, year-to-year variation can exceed 5 % due to sample noise rather than genuine change.

Comparison criteria

When we compare communes to each other or to a national average, we apply the following criteria consistently:

  • Metric: rate per 100,000 inhabitants (CEAD-published figure, as described above).
  • Year: the latest complete year for which CEAD has published a closed annual series for all communes. This is the same year for all communes in a given build.
  • Exclusion of low-population communes: communes with fewer than 10,000 inhabitants are excluded from national and regional rankings due to statistical volatility (DATA-04 rule). Their pages remain accessible but note the exclusion.
  • Ranking basis: the national rank shown on commune pages is computed across all non-low-population communes in Chile (currently 346 total communes, of which a subset meet the population threshold). Rank 1 = lowest reported rate in Chile for that year.
  • National average definition: the unweighted arithmetic mean of non-low-population commune rates (see rate calculation section above). Not the CEAD national sum.

We compare communes only to the national mean or to regional peers — not to international figures, because reporting standards, legal definitions, and demographic structures differ substantially across countries, making cross-country rate comparisons unreliable.

What this site does NOT say

The following statements are not made anywhere on this site, and if you see language that implies them, please report it as a bug:

  • We do not classify any commune, city, or region as "safe" or "dangerous" in absolute terms. The map and ranking pages present relative reported incidence — lower or higher than other communes — not absolute risk levels. A commune that ranks low for reported crime is not declared "safe"; a commune that ranks high is not declared "dangerous".
  • We do not publish probability-of-victimisation figures. Reported rates are not individual risk probabilities. A rate of 1,000 per 100,000 does not mean a 1 % annual probability of becoming a crime victim — it means 1,000 police-recorded incidents per 100,000 registered residents, with all the underreporting and denominator caveats described above.
  • We do not make predictive or forward-looking safety claims. Trend indicators describe what CEAD data shows for past years; they do not predict future conditions. A "falling" trend does not mean a commune will continue to decrease.
  • We do not rank neighbourhoods within communes. CEAD data is available at the commune level only. We cannot show which barrio or street within a commune has higher or lower reported incidence.
  • We do not compare Chile to other countries. International crime rate comparisons require harmonised definitions and reporting standards that do not currently exist for the countries most relevant to our audience.

Our goal is to make official CEAD data accessible and clearly presented — not to produce safety verdicts. If you have questions about the data or methodology, use the Contact page.