Map projections, in motion
One Earth. Many perspectives.
Turn Earth to choose your view. Unfold it to discover how flat maps change our world.
Interactive map projection explorer
Preserves local anglesFamiliar shapes. Unfamiliar sizes.
Mercator’s cutoff: 85.05°
This view stops 85.05° either side of its rotated midline. The cutoff moves with your chosen center, so it may leave Antarctica fully visible.
Mercator stretches without limit toward its projection poles, so they cannot fit on a finite map.
Mollweide shows the whole Earth and preserves relative area.- Country borders
- Latitude & longitude
Mercator stops at 85.05° from the rotated midline; the rotated poles cannot fit on a finite map. The in-between shapes illustrate a transition, not a separate map projection. Once unfolding finishes, the view gently zooms out if needed to reveal the whole map.
Understanding Mercator
Familiar shapes. Unfamiliar sizes.
- What stays true
- Local angles and shapes of very small regions.
- What changes
- Area grows toward the top and bottom of this map. Which countries stretch most depends on where you center it.
- Useful for
- Exploring how familiar shapes change when a different place becomes the center of a map.
The circles stay nearly round but grow toward the top and bottom. The geographic poles no longer define those edges.
Why this map exists
Gerardus Mercator’s 1569 world map was intended to aid navigation. In its classic orientation, a constant-bearing route becomes a straight line. That useful property comes with a cost: areas grow dramatically toward the poles. Today, related Mercator mathematics also underlies many web maps. It is useful to distinguish the projection’s navigational purpose from using it to compare the sizes of countries.
The story of Mercator →Make distortion visible
Same Earth. Different sizes.
Turn on Show distortion beneath the map, then use the slider to move the orange sample. Move the orange circle away from the map’s midline. How much would a small area grow?
Sample: 60° from the map’s midline.
Mercator · flat map
Turn on “Show distortion” to see equal-area circles. Their shapes and sizes reveal distortion. The multiplier compares the local area scale for equal patches on Earth with the scale at the map’s midline (the equator in classic orientation). The orange circle follows the map’s central reference meridian. Its angle is measured from the rotated midline, not Earth’s equator. The curved grid still shows geographic latitude and longitude.
Country boundaries: Natural Earth. These views use a spherical Earth model. No flat world map preserves every combination of area, shape, distance, and direction. Why projections make tradeoffs.