Where the data comes from

Everything here is published on Taiwan's open data platform under the Open Government Data License version 1, which allows commercial use as long as the source is credited. This page lists every dataset used, how often it is refreshed, and the traps in it.

Datasets used

2,403,922 raw rows in total. After de-duplication that is 1,042,189 accidents, covering 2024/01 to 2026/09, or 33 months.

What A1 and A2 mean

A1 covers accidents where someone died at the scene or within 24 hours. A2 covers accidents with injuries, or a death after more than 24 hours. They are reported and investigated differently, and A1 records tend to be more complete. The map uses both. Switching to "fatal only" shows accidents in which someone died, which is close to but not identical with the A1 definition.

What each record contains

The raw data has 51 columns, finer than most people expect:

The map's filters currently use time, coordinates, casualties and vehicle type; the per-point detail panel also draws on hour, light, weather, accident pattern, assessed cause and party columns (age, sex), and the district pages tabulate the same columns. Speed limit, surface condition, signals and the rest are not wired up yet.

A dataset that is not used, and why

The platform also carries historic accident records (dataset/12197, covering 2013 to 2021). It was downloaded and checked: it has addresses but no coordinates. Mapping it would mean geocoding the addresses first, and the address formats are irregular enough that the result would be unreliable. That is why this map starts in 2024 rather than going further back.

Back to the map

Other tools on this site

All run on one machine at home; the data tools use Taiwan government open data and state their limits.