Zip Code Locator

[Dorsey]

I'm looking for something, either software or an algorithm, that would allow me to determine which ZIP codes surround a given ZIP code within a mileage range. I know that this is a somewhat nebulous request, but I'm looking for similar capability to map sites that locate businesses within X miles of one's home, given X and your home's ZIP code. I would hope this might be easier than implementing a map database and working at the street address level.

 

I suppose that I could obtain geographic data with map coordinates (latitude, longitude) of all known ZIP codes, and do the math. That may end up being the answer.

 

Thanks, all.

Dorsey

[Lianna]

oooph. Good luck with this one. You know? I'd never thought about how they did that!

 

[Madmanmcp]

See if this is what you need.

 

http://zipfind.net/

 

BoB/ Madman

[Dorsey]

OK. About two hours after posting this, I found what I was looking for, and have implemented a decent locator. The most informative seems to be: www.greatdata.com. Of course, they want to sell you their database and software, but there's a free demo and an explanation of how to use it. They even accomodate changing latitude in their longitude calculation.

 

Another source for info is the U.S. Census Bureau at www.census.gov/geo/www/gazeteer/places2k.html. These folks only have info from the last U.S. census (2000), but it's extensive and free. The USPS also offers ZIP Code products for $25.

 

Do a vivisimo search (or Google, if you must) on "zip code locators" and you'll find a lot of stuff.

 

Dorsey

[Dorsey]

I should have mentioned that there are almost 50,000 ZIP codes in the U.S., possessions, and territories. The algorithm to locate ZIPs within a radius of a given ZIP Code is five lines of PHP for the math and one select. Incredibly simple.

 

Dorsey