RockWare, the makers of RockWorks and LogPlot geotechnical software, have released a free online tool to convert between different coordinate systems. You can convert to and from State Plane coordinates using a NAD27 datum, and geographic latitude and longitude with a NAD83 / WGS84 datum using a pretty simple interface. There are probably a few other coordinate systems built in there as well. You can visualize your points immediately on a Google Maps interface. You can also plot up an elevation profile if you like. [Source: Convert your coordinates using Rockware.com’s free tool. Image: Wikipedia]
