Frequently Asked Questions & Answers:
Latitude and Longitude:
Q: What is latitude and longitude used for?
A: Latitude/Longitude is used to calculate the distance between
one zip code and another. Latitude and Longitude is primarily used for
locators: for finding the nearest store or dealer to your zip code.
It is also used for finding all the zip codes within a certain radius.
Q: Where can I find the formula for calculating the distance between
one zip code and another, or for developing a locator?
A: Please download a demo version of the file from our Download
Page. With the demo, we include readme help files, including
a file called, lat-long.txt. This has the formula for calculating
the distance and general logic on how to develop a locator.
Q: How many unique latitude and longitude points do you have in
A: In the U.S., we currently have about 41,000 unique latitude and
longitude points. For Canada, we have over 5,200.
Q: What format is your latitude/longitude data in?
A: The format of our Latitude/Longitude information is decimal degrees,
not degrees minutes and seconds.
Q: Do you have geocodes?
A: Yes we do have geocodes. Geocodes is just another
name for a Latitude/Longitude pair.
Q: Whats a centroid? What center point do you use for each
A: A centroid is a center point. We use centroids in our zip codes.
We try to use a population based centroid rather than a physical centroid
when possible, since thats where most of the people are. When
this is not possible, we use a physical centroid.
Q: You have the same latitude & longitude for more than one
zip code in some cities. Why?
A: When we have the same Latitude and Longitude for more than one
zip code in the same city it is usually because of multiple Post Office
Boxes at one location or new zip codes that just came out which we cant
map. But generally, all zip codes should have a unique Latitude/Longitude.