Mercator projection: interactive map

Move countries across the map, switch on distortion layers, and see what the Mercator projection changes.

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✈Great circle vs rhumb line: routes tool↗

Select map projection:

Country at the center

Find a country

Change the world's center ↗

Add country to compare:

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Quick start

Add a country, then drag its outline anywhere on the map.

Map appearance

Change the background and contrast of every layer.

Map layersProjection diagnostics

Tissot's indicatrices

Equal-sized circles on the globe. Their distortion on the map instantly reveals how the projection alters area and shape.

Area-distortion heatmap

A continuous gradient across the whole map: the redder an area, the more the projection inflates its size relative to reality.

Area isocolesA

Lines joining places with the same relative area inflation. They work like contour lines on a topographic map of error.

Angular isocolesω

Lines of equal maximum angular deformation. On conformal projections such as Mercator, this layer remains empty.

True-north field↑N

Arrows show where geographic north lies on the screen. Their rotation reveals how a projection alters directions.

Geographic context

Equator, tropics & polar circles

Five major parallels anchor Earth's zones and reveal how the projection stretches high latitudes.

Ocean currents

An animated, simplified view of major surface currents. It is especially revealing on ocean-centred projections.

Day & night

Draws the day/night boundary (terminator), a great circle that every projection bends differently. Drag the slider to change the time.

Antipodes

Overlays each selected country's outline at its antipode (the opposite side of the globe). Unavailable on the globe view.

Field guide to map errorHow do I read these layers?

Projection Details ↗The Mercator projection preserves angles but extremely enlarges areas near the poles. Greenland appears to be the size of Africa.

Atlas of error · liveMercatorClick or tap a country to add its outline

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Mercator projection at a glance

Type: Conformal Cylindrical
Creator: Gerardus Mercator
Year: 1569
Area: Highly distorted (massive surface enlargement near the polar regions)
Shape: Preserved locally (conformal projection)
Distances: Distorted (scale increases towards the poles)
Angles and directions: Preserved (true angles and directions)

Add countries from the tools panel and drag them to other latitudes. The outline keeps its true shape and area on the globe, so any change in its size on the map shows this projection's distortion. Tissot's indicatrices and the area distortion map show the same effect across the whole world.

Full guide: Mercator projection →Quiz: name the projection →