# Heatmap

> Two dimensions, shaded by value. Sample data: card transactions by weekday and hour over 7 days, the busiest cells at 398 and 412.

- Type 024 · Space and place
- Component: `<Heatmap>`, the same name as the Figma component
- Install: `npx shadcn add @chartory/heatmap` (free in Hearth: the public registry, no token; Signal with Code and Complete)
- Type page: https://usechartory.com/charts/heatmap

## Installation

1. **Set up the registry once.** This chart is free in Hearth and MIT licensed: no token. Add @chartory to components.json once (the URL alone, no headers), or skip this when another chart is already installed. [Installation guide](https://usechartory.com/docs/installation)

2. **Add the chart.** One command adds the Heatmap component to your project.

```bash
npx shadcn add @chartory/heatmap
```

3. **Use it.** Pass your rows. The props are the Figma properties.

usage.tsx:

```tsx
import { Heatmap }
  from "@/components/chartory/heatmap"

<Heatmap
  data={cardTransactions}
  size="m"
  legend
/>
```

## Props

### `<Heatmap>`

Every prop but data is a Figma property with the same name and values.

| Prop | Type | Default | Note |
| --- | --- | --- | --- |
| data | HeatmapData | Required | The chart's data. The tables below list every field. |
| size | "xs" \| "s" \| "m" \| "l" | "m" | The size class. Each one is laid out again from the data. |
| legend | boolean | true | Shows the legend row under the plot. |

### HeatmapData

The data prop: one object for the whole chart.

| Prop | Type | Default | Note |
| --- | --- | --- | --- |
| rows | string[] | Required | The row labels, in order. |
| cols | string[] | Required | The column labels, in order. |
| xl | Record<number, string> | Required | The x axis labels, by index. |
| vals | number[][] | Required | The values, in order. |
| marks? | Record<string, string> | — | The marks, by key. |
| yW? | number | 36 | The width of the y axis label column, in px. |
| gap? | number | 3 | The gap between cells, in px. |

## Heatmap: a React and Figma chart in four sizes

### What does a heatmap show?

A heatmap lays out a grid of two dimensions, such as weekday and hour, and shades each cell by its value, so busy and quiet patches show at once. Use it for transactions by hour, tickets by team and day, or any count across two axes.

Chartory ships it as a Figma component and a React component with the same name. The code installs from the shadcn registry with one command and lands in your project as a file you own.

### What is the Heatmap component?

It is one **<Heatmap>** component. Its props are the Figma properties with the same names and values, and the props table above lists them. The data is a value per cell of two dimensions.

Sizes **XS**, **S**, **M** and **L** re-lay the chart out from the data instead of scaling it, so labels stay readable at every size.

### When should I use it?

- **Are there two dimensions?** Yes means the heatmap fits.
- **Is the grid rectangular?** Yes means the heatmap fits.
- **Is shading enough?** Yes means the heatmap fits.

### When does another type fit better?

- **One value per day.** Use Calendar heatmap instead.
- **Hours around a clock.** Use Radial hour heatmap instead.
- **Sized dots per cell.** Use Punch card instead.

## Heatmap questions

### Does the Heatmap chart work with shadcn/ui?

Yes. It installs through the shadcn registry with the shadcn CLI, and the file lands in your project.

### How do I install it?

It is free in Hearth and MIT licensed: add the @chartory registry URL once, no token, then run npx shadcn add @chartory/heatmap. The Installation guide has the steps.

### Can my coding agent install it?

Yes. Connect the Chartory MCP server and ask for the heatmap chart; the agent runs the same command and you review the diff.

### What data does it expect?

A value per cell of two dimensions. The sample data comes with the component, and the props table lists every field.

### Which sizes does it ship in?

XS, S, M and L, in Figma and in code. Each size is laid out again from the data, so text and lines keep their size.

### Is it in the Figma file too?

Yes. chart/024-heatmap has the same properties as the component.

### Does it follow light and dark mode?

Yes. Every paint is a token, so the chart follows light and dark mode and the collection you pick.

### Which plan has the code?

None for Hearth: it is free in the public registry, no token. The Signal collection (@chartory/signal) comes with Code and Complete.