Aug 4, 2009
So Many Geocoder Options
Geocoding is an integral part of using mapping APIs, as it converts from human-readable addresses to latitude and longitude points that the providers understand. It’s also not particularly easy to do on your own, so you’ll likely need a provider.
Below you’ll find an extensive, categorized list of geocoding providers.
JavaScript Geocoders
- Yahoo (built-in, or use GeocodeAddress function)
- Mapstraction (a wrapper for multiple providers–see it in action)
Free Geocoder Web Services
Commercial Web Services
- Geocoder.US (four lookups for one cent)
Got any more?
I know I’ve missed some. What other geocoders need to be added to this list?
Hi, I'm Adam. I'm writing a book about developing maps on the web. This site is where I'll share the things I find and help you create your own maps. 
The geopy package wiki (http://code.google.com/p/geopy/wiki/GettingStarted) lists an additional service called geonames and says that geocoder.us is free for non-commercial purposes. Certainly, I can use geopy with geocoder.us without an account but I haven’t used it very much.
Check out cloudmade’s offering. It uses OSM for the data. I haven’t played with it myself, but have heard good things.
Does geocoder.us provide additional functionality or quality above these free services? If not, why would anyone use it rather than the others?
I think the biggest reason someone would choose geocoder.us is that it has completely open terms of service. Paying for a commercial product nearly always gives you more flexibility.
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