How HERE Calculates the Center Point for a Postal Code Search in Geocode & Search v7?

Symptoms
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Customers may observe one or more of the following:

The latitude/longitude returned for a postal code does not appear to be the exact geometric center of the postal area.
The center point is located near the edge of the postal code polygon rather than in the visual middle.
The returned point is positioned on land even though the mathematical center of the postal area appears to fall in a lake, river, or coastal waterbody.
Different postal areas produce center points that seem inconsistent when compared visually on a map.
Postal code search results return a representative location that does not match a customer's manually calculated midpoint.

Answer

HERE determines the center point of a postal code by using the polygon that defines the postal code boundary and calculating a representative centroid for that area.

In most cases, this point corresponds to the geometric center of the postal code polygon, resulting in a location that appears near the visual center of the postal code area on the map.

However, a purely geometric centroid is not always suitable for map display or geocoding purposes. Depending on the shape and geography of the postal code area, the calculated centroid may fall:

In lakes, rivers, reservoirs, or coastal waters
Outside populated areas
In locations that do not provide a meaningful visual representation of the postal code area

In such cases, HERE may adjust the representative postal code location to a nearby valid position that better reflects the postal area while remaining within the same postal code region. This ensures that the returned location is both geographically representative and practical for mapping and search applications.

Impact
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The returned point may not exactly match the visual center of the polygon.
Distance calculations based on the representative point may differ slightly from calculations based on a mathematically derived centroid.
Map markers may appear offset from the apparent center of the postal area.

Expected vs. Unexpected Behavior
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### Expected

The returned postal code location represents the postal area polygon.
The point may be adjusted from the exact geometric centroid when necessary.
The point remains within or near the represented postal area and provides a practical map location.

### Unexpected

The point is completely unrelated to the postal area.
The returned location belongs to a different postal code polygon.
The location falls far outside the intended postal area without a valid geographic reason.

Example
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Example: postal code 00100, Finland:

Postal code 3146, Glen Iris Victoria Australia:

Recommended Actions
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Use the returned postal code coordinate as the representative location for display and search purposes.
If an exact geometric centroid is required for a specific business workflow, calculate the centroid directly from the polygon geometry obtained from the relevant dataset.
When validating postal code locations, compare against the full polygon rather than relying solely on the representative point.

Products
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HERE Geocoding and Search solutions
HERE postal code and administrative area data products

Keywords / Tags
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