# Boxplot Chart

> Grouped quartile boxplots highlighting median and outlier spreads.

A shadcn/ui block from the [@paceui](https://paceui.com/?utm_source=shadcn.exchange) registry, listed on [shadcn.exchange](https://shadcn.exchange/r/paceui/tanstack-charts-boxplot).

- Page, with a live preview: https://shadcn.exchange/r/paceui/tanstack-charts-boxplot
- Screenshot: https://abzjhwgwpdpz7ua5.public.blob.vercel-storage.com/shots/paceui/tanstack-charts-boxplot-light-15718903bb3807c9.png
- Registry item: https://paceui.com/r/tanstack-charts-boxplot.json
- Listed: 2026-10-21, source last changed 2026-10-21

## Install

```bash
npx shadcn@latest add https://shadcn.exchange/r/paceui/tanstack-charts-boxplot.json
```

Run it in a project that has shadcn/ui set up. It adds the files below and installs what they depend on.

## Dependencies

- npm packages: `@tanstack/charts`, `@tanstack/react-charts`, `d3-scale`
- Registry items: `card`

## Files

### `components/tanstack-charts/bar/boxplot.tsx`

```tsx
import { type ChartPoint, boxY, defineChart } from "@tanstack/charts";
import { motion } from "@tanstack/charts/motion";
import { tooltip } from "@tanstack/charts/tooltip";
import { Chart } from "@tanstack/react-charts/core";
import { useMemo } from "react";

import { scaleBand, scaleLinear } from "d3-scale";
import { BarChart3 } from "lucide-react";

import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card";

interface BoxplotDatum {
    Expt: number;
    Speed: number;
    Run: number;
}

const motionRenderer = motion({
    initial: "always",
    transition: { type: "spring", stiffness: 170, damping: 18, mass: 1 },
});

function generateDemoData(): BoxplotDatum[] {
    const results: BoxplotDatum[] = [];
    const baseSpeeds = [850, 920, 880, 810, 890];
    for (let expt = 1; expt <= 5; expt++) {
        const base = baseSpeeds[expt - 1];
        for (let run = 1; run <= 12; run++) {
            const spread = Math.sin(run * 1.3 + expt) * 60 + Math.cos(run * 0.7) * 30;
            results.push({ Expt: expt, Speed: Math.round(base + spread), Run: run });
        }
    }
    return results;
}

function shadcnTooltipContent<TDatum>(points: readonly ChartPoint<TDatum>[]) {
    if (points.length === 0) return { title: "", rows: [] };
    const datum = points[0].datum as any;
    if (!datum) return { title: "", rows: [] };
    if (datum.kind === "summary") {
        return {
            title: `Experiment ${datum.category}`,
            rows: [
                { label: "Median", value: `${datum.median.toFixed(1)} km/s`, color: "var(--chart-1)" },
                {
                    label: "IQR (Q1 - Q3)",
                    value: `${datum.q1.toFixed(1)} – ${datum.q3.toFixed(1)}`,
                    color: "var(--foreground)",
                },
            ],
        };
    }
    return {
        title: `Experiment ${datum.category} Outlier`,
        rows: [{ label: "Speed", value: `${datum.value.toFixed(1)} km/s`, color: "var(--chart-2)" }],
    };
}

export function BoxplotChart() {
    const data = useMemo(() => generateDemoData(), []);

    const definition = useMemo(
        () =>
            defineChart(
                {
                    renderer: motionRenderer,
                    marks: [
                        boxY(data, {
                            id: "experiment-boxplot",
                            x: "Expt",
                            y: "Speed",
                            key: (row: BoxplotDatum) => `${row.Expt}:${row.Run}`,
                            fill: "var(--chart-1)",
                            stroke: "var(--chart-1)",
                            inset: 12,
                            r: 3,
                        }),
                    ],
                    scales: {
                        x: {
                            scale: () => scaleBand<number>().padding(0.25),
                            axis: {
                                line: false,
                                label: "Experiment Trial",
                                ticks: { size: 0, padding: 10 },
                            },
                        },
                        y: {
                            scale: scaleLinear().domain([700, 1050]),
                            grid: true,
                            axis: {
                                line: false,
                                label: "Speed Variance",
                                ticks: { size: 0 },
                            },
                        },
                    },
                    margin: { top: 24, right: 24, bottom: 32, left: 45 },
                    theme: {
                        foreground: "var(--muted-foreground)",
                        grid: "var(--border)",
                        background: "transparent",
                    },
                },
                {
                    focus: "group-x",
                    tooltip: {
                        use: tooltip,
                        className:
                            "font-sans shadow-none rounded-md bg-popover text-popover-foreground border p-2 text-xs",
                        anchor: "group-center",
                        placement: "auto",
                        content: (points) => shadcnTooltipContent(points),
                    },
                },
            ),
        [data],
    );

    return (
        <Card className="w-full max-w-xl">
            <CardHeader>
                <CardTitle>Experiment Speed Distribution</CardTitle>
                <CardDescription>Grouped quartile boxplots highlighting median and outlier spreads</CardDescription>
            </CardHeader>
            <CardContent>
                <div className="h-[250px] w-full">
                    <Chart
                        definition={definition}
                        renderer={motionRenderer}
                        height={250}
                        ariaLabel="Experiment Speed Distribution Chart"
                    />
                </div>
            </CardContent>
            <CardFooter className="flex-col items-start gap-2 text-sm">
                <div className="flex items-center gap-2 leading-none font-medium">
                    Trial 2 demonstrated tightest interquartile stability{" "}
                    <BarChart3 className="h-4 w-4 text-indigo-500" />
                </div>
                <div className="text-muted-foreground leading-none">
                    Boxes enclose the middle 50% of readings; whiskers extend to non-outlier limits
                </div>
            </CardFooter>
        </Card>
    );
}

export default BoxplotChart;
```