# How to convert from UTM Zone 36N Mercator to WGS 84 degrees of lat and long?

I have acquired many coordinates from a points I extracted from polygons. The points are in WGS 84 UTM Zone 36N, and I want to use them on Google Maps. I found out that they use different systems (I am no GIS expert :S) "that uses a Mercator Projection appropriate for that zone, with Units of Meters", and I want to convert them to units of degrees of Latitude and Longitude.

Example of points I have:

3390003.50135 3390003.50135

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Do you have the data in ArcMap? –  Roy Apr 25 '12 at 11:28
ya... I extracted the coordinates from the dbf file –  Ahmed Nassar Apr 25 '12 at 11:33

ArcMap has a Geoprocessing Tool that Adds XY Coordinates as two new fields in the attribute table. If you're set up in a projected coordinate system, you'll need to first change over to the geographic system in order for the output of the tool to be in Lat Long.

Alternatively you can open a new map, set the data-frame to WGS 84 (Right-click 'Layers' in the table of contents, choose properties, Coordinate system). Add your point shapefile (or feature class) add two fields for x and y coordinates, right click -> Calculate Geometry -> X-Coordinate -> Use Data frame's coordinate system.

Data Frame Properties (right click 'Layers' in TOC):

Calculate Geometry Dialog Box:

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Make sure field type is DOUBLE if you go with the second route. –  Roy Apr 25 '12 at 11:58
Yes I know all of this, the problem is the points arent correct, when I plot them on google earth, they are not in the same country or continent. I understood from people here that google earth uses different system, my coordinates are in meters, i want them degrees for google earth or maps –  Ahmed Nassar Apr 25 '12 at 12:10
Geographic coordinate systems use lat long (decimal degrees, degree minutes seconds, etc.) Which is why you need to change from projected (feet, meters, etc.) to geographic, but you know all of this. –  Roy Apr 25 '12 at 12:14
Yes. How to get the degrees is the problem i cant solve, I used online converters and they did the conversion. But i have nearly 4000 points i cant do them manually. –  Ahmed Nassar Apr 25 '12 at 12:20
The second part of my answer provides a method for getting decimal degrees in ArcMap. Once you add the two fields, you can calculate the LatLong for all 4000 points in one-feld-swoop using the Calculate Geometry method. –  Roy Apr 25 '12 at 12:23

Another option is to convert the coordinates BEFORE you import them into ARC. You can just convert UTM do decimal degrees using an online batch convertor, for example http://www.hamstermap.com where you just copy/paste your UTM coordinates.

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