D3 Choropleth World Map

Join observable to explore and create live, interactive data visualizations. It implements tooltips and zoom effects, enabling rich interactivity, deep analysis and discovery. You must have a common id between the geospatial file and the data.

D3 is a javascript library which permits to manipulate documents, based on data. In this tutorial i will build a choropleth map which shows the population of each country of the world. Choropleth map section download code.

This is the choropleth section of the gallery.

It looks like your map data is in geojson but you are trying to build it using topojson constructs. Choropleth map is a thematic map, in other words, a specially designed map not a general purpose one, which is designed to show measurement of statistical variable on the map using different color shades or patterns; From the most basic example to highly customized examples. Today we’ll walk through how to create a popular visualization;