I have a feature class with points in State Plane coordinates, and I would like to add two columns on the attributes to add the lat and long for each point.
How can I convert each point of the feature class and get its lat,long values and save them in the attributes.
There are a few different ways to do this.
1. Add XY Coordinates tool (in Data Management, Features). It checks the output spatial reference setting in the ArcToolbox/Geoprocessing environment settings, so you could set it to NAD 1983 or whatever the geographic coordinate system is that's being used by the State Plane system.
2. Add the data to ArcMap. Set the data frame's coordinate system to match what you want the coordinates to be in. Open the layer's attribute table. Add two new fields of double type. Right click a field and select calculate geometry. That dialog will let you use the data or data frame's coordinate system.
If you want anything other than a point's coordinates or the centroid of a polygon, you would have to use the Field Caculator.