Rechart

Recharts — Skill

Name: recharts Purpose: Build responsive, readable charts with Recharts using correct data mapping and composition. Use this skill whenever creating charts with Recharts.

Applies when: Using LineChart, BarChart, AreaChart, PieChart, ResponsiveContainer. Do not use when: Charts are not built with Recharts.

Rules

• Always responsive: Wrap charts in ResponsiveContainer and ensure a fixed height parent.
• Explicit data model: Normalize data and use stable dataKey values.
• Pick the simplest chart: Use LineChart for trends, BarChart for comparisons, AreaChart for cumulative/volume, PieChart for part-to-whole.
• Interactivity: Add Tooltip; add Legend when multiple series exist.
• Performance: Disable animation for large/static dashboards and reduce point count.

Workflow

1. Define the data shape and stable keys.
2. Choose the simplest chart that answers the question.
3. Wrap in ResponsiveContainer with a height.
4. Add axes, tooltip, and legend as needed.
5. Disable animation or aggregate data for large sets.

Checklists

Implementation checklist

• Chart is wrapped in ResponsiveContainer
• X/Y axes are present when needed
• Tooltip shows correct units
• dataKey matches field names

Review checklist

• Animations disabled for large datasets
• Colors are accessible

Minimal examples

Line chart (trend)

import {
  LineChart,
  Line,
  XAxis,
  YAxis,
  CartesianGrid,
  Tooltip,
  Legend,
  ResponsiveContainer,
} from "recharts";

export function SalesChart({
  data,
}: {
  data: Array<{ month: string; sales: number }>;
}) {
  return (
    <div style={{ height: 320 }}>
      <ResponsiveContainer width="100%" height="100%">
        <LineChart
          data={data}
          margin={{ top: 8, right: 16, bottom: 8, left: 8 }}
        >
          <CartesianGrid strokeDasharray="3 3" />
          <XAxis dataKey="month" />
          <YAxis />
          <Tooltip />
          <Legend />
          <Line type="monotone" dataKey="sales" dot={false} />
        </LineChart>
      </ResponsiveContainer>
    </div>
  );
}

Custom tooltip

type TooltipProps = {
  active?: boolean;
  label?: string;
  payload?: Array<{ name?: string; value?: number | string }>;
};

export function CustomTooltip({ active, label, payload }: TooltipProps) {
  if (!active || !payload?.length) return null;
  return (
    <div className="rounded-md border bg-white p-2 text-sm shadow">
      <div className="font-medium">{label}</div>
      <ul className="mt-1 space-y-0.5">
        {payload.map((p, i) => (
          <li key={i}>
            {p.name}: {p.value}
          </li>
        ))}
      </ul>
    </div>
  );
}

Common mistakes / pitfalls

• Missing ResponsiveContainer or fixed-height parent
• Mismatched dataKey values
• Over-animating large dashboards
• Rendering too many points without aggregation