Many world maps are centered on the prime meridian through Greenwich, so Europe and Africa sit in the middle while the Pacific Ocean is split at the edges. That is a convention, not a property of the Earth: a sphere has no single center. This tool lets you put any country in the middle.
Before flattening, we rotate the geographic grid so the chosen country lands in the middle of the map. Areas on the globe stay the same. Changing the center does not remove a projection's distortion; it moves it elsewhere: shapes are most faithful near the new center and most distorted at the edges of the map.
In “Exactly at the center” mode, geographic north does not point up everywhere on the screen. In “On the central meridian” mode we only change the central meridian, so north stays up and the country keeps its latitude.
Australia at the center joins the Pacific Ocean into one piece, while the Atlantic is split at the edges of the map. Every country has its own address you can share.
No. Every flat map distorts the globe, and the choice of center is the mapmaker's decision. A map centered on Australia or Poland is just as correct as one centered on Greenwich, as long as it uses the same projection.
A map centered on the prime meridian has its edges at the 180° meridian, which runs through the middle of the Pacific Ocean. The ocean therefore appears on both edges. Putting a country from East Asia or Oceania at the center joins it into one piece.
Not on the globe. On the map it depends on the projection: Equal Earth keeps area proportions in every setting, while oblique Mercator enlarges areas near the new poles of the projection.
