Coordinates to country

Worked example: two tricky points

A point at 66.5° N, 25.7° E, in Finnish Lapland, returns Finland. A point at 16.85° S, 179.95° W, on Fiji's island of Taveuni, returns Fiji. Both are hard cases for a simple flat test, because Russia and Fiji have land on both sides of the 180° meridian and their outlines wrap around the map. The spherical test used here handles them.

How to use it

1. Paste coordinates into Paste coordinates and click outside the box, or click the map, search, or use GPS.
2. The first lookup loads the world outline file. Later lookups are instant.
3. The country name appears under the coordinate card. A message that there is no country polygon means the point is at sea or on a very small island.
4. Click any of the six coordinate values on the card to copy it.

How the test works

The page downloads the world-atlas file of country outlines once. For each lookup it runs a point-in-polygon test on the sphere from the d3-geo library against each country until one contains the point. No coordinates leave your browser for this step.

This is the same method used by the country finder, which adds GPS and ISO codes.

Coastlines, islands, and borders

Natural Earth's 1:50m scale is designed for world and continent maps. Coastlines are smoothed, so a point on a beach can fall in the sea. Small islands can be missing altogether and return no country. Borders are smoothed too, so points within a short distance of a border can land in the neighbor.

For US points, the coordinates to state tool uses much more detailed Census outlines.

Disputed areas

Natural Earth maps de facto boundaries, the lines where control sits on the ground. In disputed regions the country returned follows that choice, which may differ from the claims of one or more governments. Treat results there as descriptive, not as a legal statement.

Common uses

It helps label rows in a dataset by country, check where a ship or balloon was at a moment in a log, and settle which country a remote point belongs to. For many rows, run the points through a GIS tool with the same Natural Earth file. This page is built for checking a few at a time.