NADCON is the standard NAD27-NAD83 datum transformation program, created by the United States National Geodetic Survey. Transformation is derived from a minimum curvature surface from the National Geodetic Reference System. Approximate accuracy of 0.15-0.50 meter. NADCON is the fastest, simplest, and most accurate datum transformation for mapping at scales of 1:200 and smaller and is intended for conversion of NAD27 to NAD 83 in the continental United States, Puerto Rico, and the Virgin Islands.
- NADCON computations to convert latitude and longitude from NAD 27 to NAD 83 or from NAD 83 to NAD 27