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The precision of lat/long coordinates

posted by Jason Kottke   Sep 05, 2014

Let’s say you have latitude/longitude coordinates of 40.742041, -73.989579 (my current location). How precise are those 6 digits after the decimal point? Well, five decimal places will get you to within a meter and six will get you to within 11 cm:

The fifth decimal place is worth up to 1.1 m: it distinguish trees from each other. Accuracy to this level with commercial GPS units can only be achieved with differential correction.

The sixth decimal place is worth up to 0.11 m: you can use this for laying out structures in detail, for designing landscapes, building roads. It should be more than good enough for tracking movements of glaciers and rivers. This can be achieved by taking painstaking measures with GPS, such as differentially corrected GPS.

(via teendrama)