World borders drawn as lines
TopoJSON boundaries rendered as a line layer rather than a fill. Topology shares arcs between neighbours, so border lines are drawn once instead of twice, which removes the doubled-stroke artefact at shared edges.
Start an editable copy with this data and your current map styling.
What to look at
- Topology means shared arcs are stored once, so borders have no doubled stroke.
- A boundary-only rendering is often clearer than a fill when the data is the lines.
- The Mono theme keeps the boundary layer clear in a restrained print-style palette.
Source columns
These fields describe the example data. CSV and Excel use first-row headers; GIS formats store geometry and feature properties. Required geometry depends on the map type.
| Column | Type | Example |
|---|---|---|
| name | text | Mongolia |
| geometry | geometry | Polygon |
Rebuild it with your own data
- 1
Get your TopoJSON file ready
The example fields are name, geometry. For CSV or Excel, put headers in the first row. GIS files carry geometry and feature properties. Prepare any grid, catchment or route geometry before import.
- 2
Drop it into the studio
MapCrafter detects the geometry, counts the features, and shows the layers it found.
- 3
Style the imported layer
Pick which column drives colour, and which drives size or width where relevant.
- 4
Pick a basemap theme
Mono is used here. 15 other basemaps are available, including official OpenFreeMap styles. Switch using Layers & basemap.
- 5
Share or export
Publish a link, embed the map, or export a PNG at print resolution.
Questions about this example
- What file format does this boundary lines use?
- This example illustrates TopoJSON data. The live preview uses GeoJSON geometry. MapCrafter reads TopoJSON directly, along with Excel, CSV, KML, KMZ, GPX, GeoJSON, TopoJSON and zipped Shapefile. No conversion step and no desktop software.
- What columns does the source data need?
- The file used here has 2 columns: name, geometry. For tabular imports, supply coordinate columns, WKT or GeoJSON geometry, or address columns for an explicit geocoding step. Polygon and line files carry their geometry separately from these attributes.
- Can I use my own data with this map type?
- Yes. Open the studio, drop in your file, and MapCrafter detects the geometry and applies a starting style. Then style the layer and choose which property drives colour, size or width. The studio can render a point heatmap, but grids, routes and catchment polygons must be prepared before import.
- Can I export or share the finished map?
- Each map can be published to a short share link, embedded in another page with an iframe, or exported as a print-resolution PNG. The cleaned-up geometry can also be exported as GeoJSON. All of that is available on the free tier.
- Where does the data in this example come from?
- Natural Earth 5.1.2 country boundaries: 50m coastlines supplemented with 10m small territories. Shared TopoJSON arcs are rendered once as line geometry.
More choropleth maps examples
Gallery (314)- GeoJSONPopulation across Europe, country by countryA continent cut from the same world boundary set, filled from a two-column table. Countries the table has no row for stay grey, so a gap in the data is visible rather than filled in.
- GeoJSONPopulation across Asia, country by countryThe most populous continent as a choropleth, with the two extremes — China and India against the smaller states — handled by the ramp rather than flattening everything into one colour.
- GeoJSONPopulation across South AmericaCountries and territories across the continent, filled by population. A small enough set that every shape is legible at once, which makes it a good demonstration of a choropleth with no outliers to hide behind.
Last updated 2026-10-22