Heatmaps
A heatmap visualizes the density or intensity of point data as a smooth, color-graded surface. It is ideal for showing concentrations — e.g. accident locations, population density, or environmental readings.
Creating a heatmap
- Import a GeoJSON or Shapefile layer that contains point geometry.
- Open the Style Editor for that layer.
- Set Layer type to Heatmap.
Style options
Color scale
The color scale maps density values to colors. Lower values (sparse areas) use colors at the start of the scale; higher values (dense areas) use colors at the end.
Available presets:
| Preset | Description |
|---|---|
| Plasma | Purple → yellow, perceptually uniform |
| Inferno | Black → yellow, high contrast |
| Viridis | Blue → green → yellow, colorblind-safe |
| YlOrRd | Yellow → orange → red, intuitive heat |
Density radius
Controls how far each point "spreads" its influence. A larger radius produces a smoother, more blended surface. A smaller radius reveals individual clusters more clearly.
- Fixed — constant pixel radius regardless of zoom level
- From dataset — reads radius from a numeric attribute column
Intensity
A multiplier applied to each point's contribution before density is calculated. Increase this to make sparse data more visible; decrease it to reduce the dominance of dense clusters.
Opacity
Overall transparency of the heatmap layer, from 0 (invisible) to 1 (fully opaque). Useful when layering a heatmap on top of other data.
Performance notes
Heatmaps with more than ~100 000 points may render slowly on lower-end hardware. Consider simplifying your dataset or increasing the density radius to reduce the number of distinct influence zones.