Also called choropleth

Choropleth maps

A choropleth colours regions by a value. Import polygons with a numeric property and choose that column for colour, or start from a built-in boundary dataset. The examples also include categorical area maps and boundary outlines; these show geography without implying a measured statistic.

What a choropleth map is

The studio offers 275 boundary datasets, including world countries, national subdivisions, US counties and congressional districts. They are source snapshots with varying coverage and detail; a single-boundary dataset has no internal subdivisions.

Add a source through “Add a region map”. To use values from your own table, join them to polygons before importing. The studio does not automatically match a separate region-value spreadsheet to a boundary layer.

Sequential ramps suit ordered values; categorical palettes distinguish groups. Quantile, equal interval, Jenks and manual breaks are available. Check the legend and source year, and consider rates or densities when region populations differ greatly.

Use it when

  • One value per region, attached to its polygon geometry
  • Comparing rates, densities or groups across meaningful boundaries
  • Showing regional geography with a clear source and date

Reach for something else when

Large regions dominate area maps. For point locations or totals that should be compared independently of land area, consider pins or proportional symbols.

Choropleth maps examples

280 live maps, each listing its source format, its columns and the provenance of the data.

choropleth map questions

Can I colour regions from an Excel table?
The studio does not automatically join a separate table to boundaries. Prepare a polygon file with the values attached, then choose the value property for colour. Built-in boundaries can be added separately.
What does grey mean?
On a numeric map it can indicate a missing or invalid value. Read the legend: a categorical or single-colour map can use grey for a different purpose.
Are all regional examples statistical choropleths?
No. Some use dated population or indicator data; others use adjacency colour groups or a single boundary. Each example names its map type and explains its data.