How accurate are geocoding API's and what is the most accurate?

Question

I'm creating an application with google maps api with geocoding functionality. Obviously, I want to use the api that is the most accurate. I'm giving the application an address and I need to find it on a map, but I would be ok with just finding the latitude and longitude, and then I can use that to incorporate it into whatever map api I choose. Out of your experience, which api is the most accurate? Google, Yahoo, Bing, etc. And if you could give an approximate percentage that would be great. So far I'm using Google, as it seems to be the most robust, but I would consider changing for more accuracy.

Answer 1

All of the free services are only going to be accurate to a road segment. For each road segment they store the start and end street numbers, and then interpolate. This saves processing time and disk space, it also adds some resilience against new buildings. However, it does result in evenly distributed addresses or clumping depending on how the street numbers are allocated in real life. Also side-of-street rules may not be consistent. Hence the free and low cost services are not considered good enough for emergency services and even some urban planning.

You mentioned robustness, a good fix for this is to use multiple APIs. use the most robust first. if that fails, your program can try a different one.