Why does a country change size on a map?

A country does not change area when its outline is moved. A flat map changes the scale used to draw it. This guide shows that change at one latitude, then connects it to the three views in our map.

Close view of a printed globe showing Europe and Asia — A globe keeps geographic areas on a curved surface; the diagrams below show what happens when that surface is drawn flat.

Move the same small circle north

Each row begins with an identical small circular patch at the equator. The second outline shows how the same patch appears at the selected latitude. Circle shapes here describe local distortion; a whole country spans many latitudes.

Latitude: 60° N

Wide world

East–west stretching grows with latitude. North–south scale stays fixed.

2.0× apparent area

Mercator

Both directions stretch equally, preserving local angles while inflating area.

4.0× apparent area

Equal Earth

At the map’s center, east–west stretch is balanced by north–south compression. Area stays constant.

1.0× apparent area

At 60° north, a small area looks about 2× its equatorial map area in the wide world view, 4× in Mercator, and unchanged in the equal-area view.

What the three views preserve

The default desktop map is equirectangular, also called Plate Carrée. Longitude and latitude form an even rectangular grid, so the complete world fits a broad frame. Distance along a meridian has a constant scale in the spherical model, but the east–west scale grows toward the poles. It does not preserve area or shape away from the equator.

Mercator enlarges both local directions by the same factor. Small shapes keep their angles, a useful property for navigation, while high-latitude area grows dramatically on the page. Its poles cannot be shown at a finite height, so the map clips them near 85°.

The third view uses Equal Earth, a world projection designed to preserve relative area while keeping a recognizable outline at high latitudes. Its sides curve inward toward the poles instead of stretching every latitude across a rectangle. Shapes still change, so the written area figures remain the clearest numerical answer.

Try one country in each view

Open Greenland at its original position in the wide world view, Mercator, and the equal-area view. The selected outline follows the same boundary data each time. Then drag it toward India; the fixed area figure helps separate real size from the drawing.

Russia makes the same point across a much wider range of latitude. Its northern and southern parts experience different local scale factors, so a single number for “Russia’s Mercator distortion” would be misleading. Open Russia on the map and switch views while its outline is at home.

How the diagram is calculated

The circles show the local scale of the spherical formulas used by this site. At latitude φ, the wide world view stretches east–west distance by 1/cos φ and keeps north–south scale at 1. Mercator stretches both by 1/cos φ, so its local area multiplier is 1/cos² φ. The Equal Earth row shows its local scale along the central meridian: east–west and north–south factors are reciprocal, leaving area unchanged. Away from that meridian its local shape also shears, so the small ellipse is only a central-meridian example. These factors compare each view with its own equatorial scale; they are not whole-country area estimates.

A moved country is rotated on a sphere before being drawn in the chosen projection. The area guide explains how its fixed number is calculated from source boundaries.

Sources

The projection properties and equations are documented by PROJ: equirectangular, PROJ: Mercator, and PROJ: Equal Earth. The U.S. Geological Survey’s overview explains why no flat world map can preserve every geographic property.