Where the data comes from, and how accurate it is – POSTCODEZIP US

Sources

Our database is built from a mix of authoritative public sources, national postal operators and government bodies among them, and private sources. Figures are cross checked against official references before publication.

Coordinates

Street and address files carry Latitude, Longitude and Elevation (m). Two columns tell you how precise each point is.

Geocoding Level	Meaning	Accuracy Radius (m)
ADDRESS	Point located at house number level	50
STREET	Point located on the street	50
CITY	Point located at city level	1 000
POSTAL_CODE	Point located at postal code level	5 000
NOT_AVAILABLE	No coordinate available for this row	empty

When street level positioning is not available for a row, the best possible level is used, city or postal code, and the two columns say so. Nothing is invented.

Coordinates are not present for every country. Latvia, for example, is delivered without latitude and longitude on its postal codes. The free sample shows immediately whether a country carries coordinates.

Completeness

Data comes from official sources and is as complete as those sources allow, but no national dataset is complete to the last row. Two normal situations often surprise customers.

Cities without their own postal code. In several countries, including Sweden, a locality shares the code of a neighbouring one. There is nothing missing: the country simply works that way.
Small localities and districts. Hamlets and districts that are not autonomous administrative entities are sometimes absent.

If you find a real gap, tell us with a few concrete examples. We check with the technical team and, when the gap is significant compared with publicly available data, we produce an updated file at no extra charge.