Reverse Geocoding

Understanding what makes a quality process

Reverse geocoding is the process of taking a spatial location, typically a longitude and latitude, from a mobile device such as a GPS pinger or a smartphone and converting that information to a physical location on the earth’s surface.  Typically, that location is a street address although in some applications the location is simply a track on a rail system or a ship at sea’s location.

When a street address is used it might identify the location of a delivery vehicle, a school bus, a car, or even a person walking down a street.  The purpose of this information is typically used for marketing and quality assurance.  Where are the locations where my customer’s phones identify they live?  Where is there a concentration of prospects?  In the case of quality assurance, where is the truck on the route at this time?  What area has been covered by my delivery personnel? 

The problem is that all reverse geocoding is not created equal.

The Speed Problem: Some reverse geocoding applications and API’s are extremely slow due to the calculations that have to be made.  Also, some cannot handle a stream of longitudes and latitudes being presented in near real time.

The Application Specific Problem: Some reverse geocoding applications are designed specifically for a certain software product or application and are not extensible to other uses

The What Address is This Problem: Here is where there is a great disparity in reverse geocoders. 

  • Street File Line: Many mapping applications offer reverse geocoding, but they simply use the street line interpolation method to approximate and address.  There is no reason to believe that this location is actually a real address.
  • Zip4 Method: Several of the reverse geocoding applications use the Census Bureau Zip4 file to locate the nearest Zip4 to the input longitude and latitude.  In some cases this may be adequate, but not for more sophisticated tracking and marketing uses.
  • The TIGER Address Point File: Several of the reverse geocoders use the address point file available at no cost from the US Census Bureau.  This file is from the year 2000 census and is not even remotely complete.

Why consider Willowbend’s reverse geocoder?

  1. The Willowbend reverse geocoder performs in mili-seconds for most reverse requests
  2. The Willowbend reverse geocoder is a REST web API that can be integrated into your applications easily
  3. The Willowbend reverse geocoder handles streamed longitude and latitude information in the cloud based API
  4. The Willowbend reverse geocoder uses one of the largest standardized address files available to identify the closest address (usually within 40 feet).
  5. The Willowbend reverse geocoder provides more information than just the address including standard postal information as well as some demographic information

To license the Willowbend reverse geocoder contact Support at or phone us at 469.522.2536

Transactions are priced at $3.25 per thousand.  Enterprise licenses are available