Treemap
Squarified treemap for visualizing part-to-whole hierarchical data.
Category: chart · WCAG 2.1-AA · chart, treemap, hierarchy, part-to-whole, data-viz
Props
| Prop | Type | Default | Description |
|---|---|---|---|
data | { id: string; label: string; value: number }[] | — | The hierarchical data to render as nested rectangles. |
title | string | — | Title text for the component. |
description | string | — | Supporting description text. |
width | number | — | Fixed SVG width in px. ⚠ **Omit for a responsive chart** — the chart fills and tracks its container via a ResizeObserver; there is no correct pixel number in a responsive grid. A fixed width is clamped to the container (max-inline-size: 100%) so it can never overflow its card, but it also stops the chart growing. `useChartSize` is NOT needed for this — charts call it internally. |
height | number | 320 | SVG height in px. Unlike `width`, height does NOT track the container — this is the knob you set to change the chart's aspect. |
className | string | — | Additional CSS class names merged onto the root element. |
plain | boolean | false | Marks only — no axes, grid lines, or legend. For micro/inline charts. |
Design tokens
--cascivo-chart-1--cascivo-chart-2--cascivo-chart-3--cascivo-chart-4--cascivo-chart-5--cascivo-chart-6--cascivo-chart-7--cascivo-chart-8
When to use
- Showing part-to-whole proportions across many segments in a compact area
- Visualising hierarchical magnitude where slice size encodes value
When not to use
- Few segments where a simple split reads better — use PieChart for ≤5
- Precise value comparison — area encoding is approximate
Examples
Basic treemap
import { Treemap } from '@cascivo/charts'
const data = [
{id:'a',label:'Alpha',value:40},
{id:'b',label:'Beta',value:25},
{id:'c',label:'Gamma',value:20},
{id:'d',label:'Delta',value:15},
]
<Treemap data={data} title="Market share" />