At the moment I have a web app that uses Google Maps APIs to get distance between one location (store) and a list of other locations (techs), as its all cached in a DB, it only has to run once. But its very slow that first time....

What im needing to do now is make a front end for customers, where they can enter in their address and find the closest store. As there is a tone of stores, trying to get addresses of each store and comparing it with the customers address using Google Maps API is going to take forever.

So what techniques are available to make this faster? Is it possible to filter out most of the addresses with the difference of lat and long? Or is their an API method that I can give Google Maps with a long list of addresses and have it return the closest address?