I have 1000's of data point I need to convert from North Central Texas 4202 into Lat/Long decimal degrees. Can someone give me a conversion equation so I can quickly convert using excel? I have only been able to find online conversion calculator which convert one entry at a time. This is not time efficient for me. Please help!
Since you have ArcGIS 10.1 available, it would be easy to import your current data in excel format, plot the XY coordinates in the current coordinate system, reproject your points to your desired coordinate system, and then export the data back to a new spreadsheet.
To do this, follow these steps:
1.) Add your existing spreadsheet to ArcMap
2.) Right click your spreadsheet in the table of contents and select "Display XY Data"
3.) Once your points are plotted, right click your plotted data in the table of contents and select data -> Export Data. Save the plotted points to a shapefile and add it to your map.
4.) Reproject the shapefile to the desired projection.
5.) In the Data Management -> Features toolbox, run Add XY Coordinates on your newly projected shapefile. You may have to rename your existing XY fields if they are named POINT_X and POINT_Y, as these are the field names the tool uses. This will add the XY coordinates in the new coordinate system to your attribute table.
6.) Open the attribute table of your shapefile, under table options select Export. Choose an appropriate format and location to save your spreadsheet to.
Voila, you have a new spreadsheet with projected XY data. If your ultimate goal is just to get the data into shapefile format in the correct projection, just do steps 1-4.
Assuming that your data is in a csv file (or similar) you can load data using the