Comment by jonathanoliver

Founder of Smarty here, so there's some obvious bias.

We've been in the geocoding space for over 12+ years. A geocoding API should be easy to set up, deliver rooftop-accurate geocodes, be transparent about accuracy, persist in perpetuity, have a clear pricing structure, and be lightning fast.

Smarty has geocodes for 210 million US addresses, including 20 million non-USPS addresses. Our US Rooftop Geocoding product is 97% accurate to the rooftop or parcel of the property. Perpetual use of our geocoding data is also available, and Smarty does have licensing available for re-syndicating lat/long points in your APIs. Our entry-level plans for US Rooftop Geocoding have rate limits of 25,000 addresses/second. (Most customers won't reach this speed, but you're welcome to try.)

The best way to determine a company's geocoding accuracy is to test their products directly.