ZIP Code Distance Wizard

The ZIP Code Distance Wizard performs ZIP Code distance calculations based upon ZIP Code map regions.  This software does not use roadways to determine distances.

In most all instances, ZIP Codes are assigned by the US Postal Service to oddly shaped geographic regions, often determined by physical landmarks such as roads, bodies of water, city limits, etc.  When trying to measure distances between ZIP Codes, therefore, one encounters the dilemma of what to measure between. This dilemma is no different than trying to determine the distance between North Dakota and South Dakota. If you were asked this question while standing on the border to both states, the answer would be zero.  But if you were standing on the border between North Dakota and Canada, and asked "what's the distance between North Dakota and South Dakota, you might reply, "210 miles". If, however, you were to fly from the North Dakota/Canada border to the South Dakota/Nebraska border, you might answer, "455 miles."  So the answer to the question, "what's the distance between North Dakota and South Dakota" could be anywhere between 0 and 455 miles.

The same problem exists when dealing with ZIP Codes. What should one measure between? Post offices? No, for not every ZIP Code region has a post office within its limits. For example, in the map below, mail delivered to ZIP Code 22405 is actually performed by a post office outside of the 22405 region.

So again, how does one measure between two ZIP Codes? What our ZIP Code Distance Wizard software does is use the centroid, or center of mass, for each ZIP Code region. In the map below, the two red dots are the centroids for their respective ZIP Codes. When one measures between these two center points, a distance of 12.94 miles is obtained.

Another thing to be aware of is that when searching for ZIP Codes that fall within a user specified radius distance, some ZIP Codes might be left out of the results if the centroid for the ZIP Code does not fall within the specified radius. For example, in the map above, if the user were to ask for all ZIP Codes that are within a 9 mile radius from ZIP Code 22405, the neighboring 22406 ZIP Code would NOT be included in the results.  Why?  Again, since distances are calculated based upon the centroid of a ZIP Code map region, in this case the centroid for 22406 is further than 9 miles away from the centroid for 22405, even though a circle with a 9 mile radius would overlap the eastern side of 22406.

To download an evaluation copy of the ZIP Code Distance Wizard software program that you can use on your own PC computer, click on the "Download now" link below: