>Does anyone have suggestions on software or a database that can be used to calculate the driving distance between two zipcodes. We have used ZipFind but that just uses the lattitude/longitude to calculate distance. We need to calculate driving distances. MS Mappoint does it but it's way to slow. The US Postal service doesn't seem to sell information that contains distances, they just have lattitude/longitude of the center of the zipcode. Any suggestions?
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>Jeremiah Johnson

We have a database (used to be shareware, but that concept didn't work) anyway; we include latitude/longitude and a formula on how to calculate distances between the two or to gather all information x miles away from a point.

http://www.jassing.com/zipcode/