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ChargeMap NZ
Home/How ChargeMap is built

How ChargeMap is built

One source, openly licensed, with the gaps left visible rather than filled in with guesses.

Source · OpenStreetMap contributors (ODbL) · Data 2026-08-07 · Reviewed Aug 2026 · Method

Source

Every station comes from OpenStreetMap, queried through Overpass, filtered to amenity=charging_station within New Zealand. 578 sites, extracted 2026-08-07, reused under the Open Database Licence and attributed on every page.

Open Charge Map is the other obvious source and is in some respects better, particularly on connector-level detail. It requires an API key, and building the site behind a credential that did not yet exist would have meant shipping nothing. OSM needs no key, is already licensed for this, and the same Overpass pipeline already runs for another site in this project. Each station records its provenance, so OCM data can be merged later without the two becoming indistinguishable.

Power ratings

OSM's power tags are free text and mappers write them every possible way: 50000, 50 kW, 50kw, 22. Values are parsed with the rule that anything at or above 1000 is watts, and anything outside 1–400 kW is discarded as a mis-tag. A value that cannot be parsed produces no power figure rather than a guessed one — which is why 383 sites show "not recorded".

Which town a charger belongs to

OSM marks a city with a single node at its civic centre, so simply taking the nearest named place files east Auckland's chargers under whichever village node happens to be closer. A city therefore claims sites within 25 km and a town only within 15 km, with cities checked first. Sites more than 30 km from any town are listed but not filed under one.

Which sites get their own page

A station page exists only where OSM records a power rating or a connector list — 290 of 578. A page that can say nothing but "this exists" is a thin page, and it earns no reader anything. The remaining sites still appear in the full list and on their town's page.

What this site will not tell you

Availability. Not whether a plug is free, not whether it is working, not whether it is still installed. A static page cannot know, and a stale "available" is the one error here that could strand somebody. Live status comes from the operator's app, always.

Prices. No operator tariffs are published, because there is no licensed feed for them and a quoted price goes stale silently. The cost figures are labelled scenarios with the arithmetic shown.

Per-model charging times. Not until verified battery and DC-rate figures can be cited for the New Zealand fleet. See the charging-time guide.

Gaps are the map's, not the territory's

Where a field says "not recorded", that means OpenStreetMap has no value for it — not that the charger lacks the feature. OSM takes edits from anyone, so a missing connector list is a fixable thing rather than a permanent one.

Also from this project

RunCost

What a petrol or diesel car costs per kilometre, from official test figures — the number to hold this one against.

Compare running costs →

TireFit

Tyre sizes, fitment and speedometer error — EVs are heavy and go through tyres faster.

Check a tyre size →

SkyWatch NZ

Sunrise, sunset and last light for 192 New Zealand places.

Plan the daylight →