Experimental Projection LabD3 · TopoJSON · SVG

Redefine the Equator

Tilt the equator on the globe and see Mercator stretch the world in new directions.

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Custom Mercator Projection Guide

Move the equator and reshape the Mercator projection

Mercator distortion depends on distance from the equator. This lab lets you redefine that line of least distortion, then watch the same projection stretch the world from a new centre in real time.

How the projection lab works

  1. Move the red equator handle across the 3D globe.
  2. Watch the flat Mercator map recalculate immediately.
  3. Move highlighted countries to compare distortion.
  4. Export the map alone or a combined map-and-globe PNG.

Why Mercator distorts the world

Mercator preserves angles and local shape for navigation, but it cannot keep area on a flat surface. Scale grows toward the chosen poles, so land far from the custom equator appears larger.

Custom Mercator projection FAQ

What is a custom Mercator projection?

It is a Mercator map where you choose where the line of least distortion sits. Moving that line shows how the same projection stretches the world from a different centre.

Why does the Mercator projection distort country sizes?

Mercator preserves angles and local shapes for navigation, but it cannot preserve area on a flat sheet. The scale factor grows toward the poles, so land far from the equator looks much larger than it is.

What happens when you move the equator?

Countries near your chosen equator shrink toward their true scale, while countries far from it inflate. It makes the trade-off behind every flat map visible.

Can any flat map avoid distortion entirely?

No. No flat map can keep area, shape, distance, and direction all correct at once. Every projection, including Mercator, sacrifices some properties to preserve others.

Tiny to Vast turns projection trade-offs into something you can move and inspect.