Coordinate precision and floating-point rounding errors
Storing or computing coordinates using the wrong numeric type can introduce rounding errors on the order of meters, entirely separate from any error in the original geocoding.
Tag
#coordinates
What happens to geocoding near the poles
Near the poles, longitude lines converge to a single point and time zones become almost meaningless. Location software built around ordinary assumptions tends to behave strangely there.
The International Date Line and the requests that cross it
Two points a short distance apart can be on different calendar days entirely, purely because of where the International Date Line happens to run between them.
Calculate distance between two geocoded points
Geocode two addresses to get their coordinates, then calculate the distance between them using standard great-circle math you already have in your own code.
Why "just use lat and lon" oversimplifies location precision
A pair of coordinates looks like the whole answer, but without knowing how they were derived, two identical-looking coordinate pairs can carry very different reliability.
Why coordinate rounding matters more than people think
Trimming decimal places on a coordinate looks harmless, but each digit represents real distance on the ground, and rounding too aggressively can move a point by meters or kilometers.
Coordinate reference systems: why WGS84 is the default
Every set of coordinates is defined relative to some model of the Earth's shape. WGS84 became the default for GPS and web mapping for practical reasons worth understanding.
Find the time zone for any latitude and longitude
Turn any pair of coordinates into a time zone name, current UTC offset, and abbreviation with one API call, ready for your own date library.
Reverse geocode a list of coordinates without writing a loop
Send a list of latitude and longitude pairs to the reverse endpoint in one call and get back an address for each one, in order, without extra overhead.