Question 1

Where does the crime data come from?

Accepted Answer

Crime statistics are sourced from the UK Police API (data.police.uk), which provides official street-level crime and policing data for England, Wales, and Northern Ireland. The data is published under the Open Government Licence v3.0.

Question 2

How is crime rate calculated?

Accepted Answer

Crime rate is calculated as the number of crimes per 1,000 population. This allows meaningful comparison between areas of different sizes. Population figures are based on the most recent mid-year estimates from the Office for National Statistics (ONS).

Question 3

How often is the data updated?

Accepted Answer

New crime data is typically published around the 5th of each month, covering crimes recorded approximately two months prior. This site updates shortly after new data becomes available from the Police API.

Question 4

Why are crime locations anonymised?

Accepted Answer

To protect the privacy of victims and witnesses, exact crime locations are anonymised by the police to a nearby point on a street or landmark. This means crimes are mapped to approximate locations, not exact addresses.

Question 5

What does the percentile ranking mean?

Accepted Answer

Percentile ranking shows how an area compares to similar areas. For example, a percentile of 75% means the area has a lower crime rate than 75% of similar areas. Higher percentile indicates lower relative crime.

Question 6

Why is Scotland excluded from some rankings?

Accepted Answer

The UK Police API does not include Police Scotland data. Only British Transport Police (BTP) data is available for Scottish locations, which covers a very limited area around railway stations. For this reason, Scotland is excluded from national comparisons.

Crime in Hertfordshire

Crime Overview(Nov 2025)

Crime Trend Analysis

Compared to National Average

By Crime Category

Crime Categories(Nov 2025)

Most Common

Least Common

Compare With

Towns & Cities

Data Methodology & Sources