Latitude or Longitude First?
How to read and write coordinates without getting them backwards, and why your map software might disagree with Google Maps.
The short answer
When people write coordinates for humans, latitude comes first: latitude, then longitude. That is what Google Maps, GPS units and almost every address you have ever copied use.
The big exception: GeoJSON, WKT and many GIS and programming tools put longitude first (longitude, then latitude). This single reversal is the most common reason a point lands in the wrong country.
Latitude and longitude, quickly
Latitude
- • How far north or south you are
- • Runs from -90° (South Pole) to +90° (North Pole)
- • 0° is the equator
- • North is positive, South is negative
- • The Y value on a map
Longitude
- • How far east or west you are
- • Runs from -180° to +180°
- • 0° is the prime meridian (Greenwich)
- • East is positive, West is negative
- • The X value on a map
Easy way to remember: lines of latitude are the flat rungs of a ladder (lat = ladder), so latitude tells you how high up or down you are. Longitude lines are long, running pole to pole.
The order depends on the format
There is no single universal order. It depends entirely on what is reading the coordinate. Here is who uses which.
Why GeoJSON reversed it: GeoJSON follows the mathematical convention of X before Y, and on a map longitude is the X axis. So GeoJSON deliberately writes longitude first, even though humans say latitude first. If your GeoJSON points are in the wrong place, this swap is the first thing to check. See what is GeoJSON?
How to tell if they are swapped
A value is bigger than 90
Latitude can never exceed 90. If the first number is, say, 122, it must really be a longitude, so the pair is reversed.
Your point lands at sea or in another continent
A spot you expect in California showing up near China or the Indian Ocean is the classic signature of a lat/long swap.
North and east look mirrored
If a dataset looks rotated or flipped diagonally, the X and Y were almost certainly read in the wrong order.
Signs, hemispheres and precision
What N, S, E, W mean
- • N latitude is positive, S is negative
- • E longitude is positive, W is negative
- • 37.77° N = +37.77
- • 122.42° W = -122.42
- • Drop the letter, add the sign, or keep the letter. Never both.
How many decimal places?
- • 2 places ≈ 1.1 km (a village)
- • 4 places ≈ 11 m (a building)
- • 5 places ≈ 1.1 m (a doorway)
- • 6 places ≈ 0.11 m (a person)
- • 6 places is plenty for almost any map.
Check or convert a coordinate
Paste a coordinate and instantly see it in every format. Free, runs entirely in your browser.
Frequently asked questions
Which comes first, latitude or longitude?
For human-readable coordinates and Google Maps, latitude comes first. In GeoJSON, WKT and KML, longitude comes first. Always check which format you are working with.
Is latitude the X or the Y axis?
Latitude is the Y axis (north to south) and longitude is the X axis (east to west). This is why formats that follow the X, Y convention list longitude first.
Does Google Maps use latitude or longitude first?
Google Maps uses latitude first. If you paste 37.7749, -122.4194 it reads it as latitude 37.7749 and longitude -122.4194.
Why does my GeoJSON show points in the wrong place?
GeoJSON stores coordinates as longitude then latitude. If a tool wrote them as latitude then longitude, every point will be swapped. Reversing the pair usually fixes it.