How accurate are your GeoIP2 and GeoIP Legacy databases?

MaxMind tests the accuracy of the GeoIP2 and GeoIP Legacy Databases on a periodic basis. In our recent tests, the databases were 99.8% accurate on a country level, 90% accurate on a state level in the US, and 81% accurate for cities in the US within a 50 kilometer radius. For more details, see GeoIP2 City Coverage and Accuracy.

The GeoIP2 Precision Web Services contain our most accurate data at a city/postal code level, geolocating 9% more IPs the correct postal code and 4% more IPs to the correct city in the United States than the downloadable GeoIP2 Databases.