About CrashMap
CrashMap is a free map of New Zealand roads ranked by how many fatal and serious-injury crashes each stretch is expected to have per kilometre per year. It needs no account and works in any modern browser.
Why it exists
Every year around 2,400 crashes on New Zealand roads kill or seriously injure someone, out of roughly 30,000 recorded crashes. Counting crashes alone treats a nose-to-tail in a car park the same as a head-on on an open road. CrashMap weights every recorded crash by how likely it was to be serious, so the roads that rise to the top are those where crashes tend to hurt people, not just those where crashes are common.
It is meant for anyone curious about road risk where they live or drive: residents, journalists, students, researchers and people working in road safety who want a quick, shareable view of the crash record.
Where it comes from
CrashMap was built from the experiments in a master’s project on predicting crash severity in New Zealand. The project trained and compared 86 model configurations across five model families (XGBoost, LightGBM, CatBoost, random forest and logistic regression) on Crash Analysis System records, then tested them with a rolling-origin backtest, in which each year is scored by a model trained only on earlier years. The map reads the probabilities those experiments saved; no model is refitted in the browser.
The site is designed, built and published by Tasman Tech, an Auckland web development company.
What CrashMap is not
- It is not an official NZ Transport Agency Waka Kotahi product, and it does not replace the agency’s own road safety assessments.
- It is not advice for any individual journey. A low band does not mean a road is safe.
- It does not measure risk per driver. There are no traffic volumes in the model, so busy roads rank high partly because they are busy.
How it works explains the calculation and its limits in full.
Data and credits
Crash records come from the Crash Analysis System (CAS), published by NZ Transport Agency Waka Kotahi under CC BY 4.0. Roads come from OpenStreetMap via the Geofabrik New Zealand extract (© OpenStreetMap contributors, ODbL). The base map is Google Maps. See Data and API for sources, licences and the public API.
Get in touch
Found a mistake, or want to use CrashMap in your work? Contact Tasman Tech through tasmantech.co.nz/contact.