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 your data?
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: What’s a centroid? What center point do you use for each zip code?
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 that’s 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 can’t map. But generally, all zip codes should have a unique Latitude/Longitude.