Decimal degrees

Decimal degrees are the latitude and longitude geographic coordinates as decimal fractions.
Positive latitudes are north of the equator and less than zero latitudes are south of equator. Positive longitudes are east of the prime meridian and less than zero longitudes are to the west of the prime meridian. Latitude and longitude are usually listed as "Latitude, Longitude", in that order.
Precision.
The radius of the semi-major axis (the distance from the center of Earth to the outside at the equator line) of Earth at the equator is 6,378,137.0 meters resulting in a circumference of 40,075,161.2 meters. The number of decimal places required for a particular precision at the equator is: