DumbbellChart
Show sequence, schedule or attribution over rows you prepared.
@luc/ui/chartsWhat it shows
Compare one measured quantity at two named moments, making the direction and size of change the subject.
Live preview
One measured quantity per row at two moments; the connector is the change, and its direction is the message.
<DumbbellChart
rows={[
{ label: "Latency p95", from: 412, to: 260 },
{ label: "Error rate", from: 1.8, to: 0.6 },
{ label: "Cost per run", from: 42, to: 31 },
{ label: "Coverage", from: 68, to: 84 },
]}
labels={["Before", "After"]}
format={{ kind: "number", decimals: 1 }}
height={300}
ariaLabel="Before and after"
/>Controls
Height
A chart measures its container, so it always needs a definite height.
State
The surface the chart is in — loading, empty and error are drawn by the component.
Accessible name
A drawing is not readable by a screen reader, so it needs a name that states what it shows.
The same fixture as the live preview above; the controls change how it is drawn, not what it measures.
Code
import { DumbbellChart } from "@luc/ui/charts";
<DumbbellChart
rows={[
{ label: "Latency p95", from: 412, to: 260 },
{ label: "Error rate", from: 1.8, to: 0.6 },
{ label: "Cost per run", from: 42, to: 31 },
{ label: "Coverage", from: 68, to: 84 },
]}
labels={["Before", "After"]}
format={{ kind: "number", decimals: 1 }}
height={300}
ariaLabel="Before and after"
state="ready"
/>Not controllable here
series / rows— The numbers are the caller's; the fixture above is the example.
Copy for an AI agentA specification an agent can act on: the import, the setup, the chosen props, the data contract and the accessibility expectation.
Implement `DumbbellChart` from Luc UI. It is: Show sequence, schedule or attribution over rows you prepared.
Import it with: import { DumbbellChart } from "@luc/ui/charts";
Requires: react ^19.0.0; react-dom ^19.0.0; react-hook-form ^7.0.0 (optional, for @luc/ui/forms/react-hook-form); tailwindcss ^4.0.0; node >= 22 (repository tools). Import the stylesheet once at the app root and wrap the tree in `LucProvider`. Both come from the package that publishes @luc.
Chosen configuration: `height={300}`, `state="ready"`, `ariaLabel="Before and after"`.
Accessibility: keep the component's own semantics. Do not re-implement its ARIA wiring, do not add roles it does not declare, and make sure every interactive element is reachable and operable from the keyboard with a visible focus state.
Styling: use Luc UI design tokens and the component's own props. Do not restyle with raw colour literals and do not override the component's internal structure with page CSS.
Motion: respect `prefers-reduced-motion`. The component already does, so do not disable it.
Reproduce this state:
```tsx
<DumbbellChart
rows={[
{ label: "Latency p95", from: 412, to: 260 },
{ label: "Error rate", from: 1.8, to: 0.6 },
{ label: "Cost per run", from: 42, to: 31 },
{ label: "Coverage", from: 68, to: 84 },
]}
labels={["Before", "After"]}
format={{ kind: "number", decimals: 1 }}
height={300}
ariaLabel="Before and after"
state="ready"
/>
```Usage
The values are prepared by the caller: this component draws the points it is given and computes no statistic of its own, so units, scaling and any summary have to be settled before the data reaches it.
It is drawn by the ECharts engine.
Worked examples with real data are on the family overview: Workflow & operations
import { DumbbellChart } from "@luc/ui/charts";<DumbbellChart
rows={[
{ label: "Latency p95", from: 412, to: 260 },
{ label: "Error rate", from: 1.8, to: 0.6 },
{ label: "Cost per run", from: 42, to: 31 },
{ label: "Coverage", from: 68, to: 84 },
]}
labels={["Before", "After"]}
format={{ kind: "number", decimals: 1 }}
height={300}
ariaLabel="Before and after"
/>Data contract
`rows` contain `label`, `from` and `to` numeric values; `labels` names the two endpoints; `format` describes the measure. The two endpoints should share a unit.
Important configuration
Name both endpoints, sort rows by the analytical question, and format the metric consistently on both sides.
Guidelines
When not to use
Do not use a dumbbell for a many-period time series or compare endpoints measured with different methodologies.
Configuration
| Export | Kind | Signature |
|---|---|---|
DumbbellChart | 13 documented props | ({ rows, labels, format, title, description, state, height, className, ariaLabel, ariaDescription, onReady, onEvent, eager, }: DumbbellChartProps) => import("@types/react").JSX.Element |
DumbbellChart props
Type: DumbbellChartProps
Values the compiler reads from the declaration.
| Prop | Type | Default | Notes |
|---|---|---|---|
ariaDescription? | string | undefined | — | |
ariaLabel? | string | undefined | — | |
className? | string | undefined | — | |
description? | string | undefined | — | |
eager? | boolean | undefined | — | Create the engine on mount rather than when the surface is approached. |
format? | ChartFormat | undefined | — | |
height? | string | number | undefined | — | |
labels? | readonly [string, string] | undefined | — | What the three marks mean. Default `["From", "To"]`. |
onEvent? | ((event: EChartEvent) => void) | undefined | — | |
onReady? | ((chart: EChartsInstance) => void) | undefined | — | |
rows | readonly DumbbellRow[] | — | |
state? | ChartState | undefined | — | |
title? | string | undefined | — |
Accessibility
A chart is a picture of data, so it needs a name that states what it shows, and the numbers must exist as text somewhere on the page — in a table or a written summary — because a drawing is not readable by a screen reader and cannot be copied.
What happens on the server, and when hydration changes it.
Family
Workflow & operations
Sequence, schedule, comparison and attribution.
Related