LineChart

Lines over categories with dots, curves, labels and a crosshair tooltip.

Example
import { LineChart } from "@elements/ui/chart-line";
import type { ChartConfig } from "@elements/ui/chart";

const config: ChartConfig = {
  desktop: { label: "Desktop", color: "var(--chart-1)" },
  mobile: { label: "Mobile", color: "var(--chart-2)" },
};

<LineChart data={rows} {config} x="month" curve="natural" />
<LineChart data={rows} {config} x="month" dots legend labels />

Parts

Part	What it is
LineChart	The template. One line per series through the categories.
.chart-line-mark	One line (an SVG path); --series is its color.
.chart-dot	A point marker; .is-active for the dots at the active point, .is-commit, .is-hollow.
.chart-cursor.is-line	The vertical crosshair at the active point.
.chart	The figure. Declares --color-<key> for each config entry; keeps a 16:9 box unless sized by class.
.chart-plot	The focusable plot area holding the SVG; one tab stop.
.chart-tooltip	The tooltip: heading, one row per item with swatch, name and value, optional footer.
.chart-legend	The legend row; .chart-legend-item per series, a button with legend toggle.
.chart-table	The data as a table, visually hidden unless showTable.

Attributes

Attribute	Type	Default	Description
data	Row[]	(required)	The rows: one per category.
config	ChartConfig	(required)	The chart config: per data key a label, a color (any CSS color, usually var(--chart-N)) or a theme { light, dark }, and an optional icon; legendType and tooltipType; strokeDasharray and strokeOpacity dash and fade a line or an area's edge. Each key becomes --color-<key> on the chart.
x	string	(required)	The category field.
series	string[]	[]	The value fields to draw. Empty draws every config key that has numbers in the data.
layout	"horizontal" | "vertical"	"horizontal"	vertical runs the categories down the chart and the values across it; the arrows follow them.
curve	"linear" | "monotone" | "natural" | "step" | "stepBefore" | "stepAfter" | "basis" | "bump"	"linear"	How the line joins its points.
strokeWidth	number	0	Line width in px. 0 follows the theme.
dots	boolean | { r?: number; shape?: "circle" | "square" | "diamond" | "commit"; colorByRow?: boolean; nameKey?: string; hollow?: boolean }	false	A marker on every point. colorByRow fills each from its row's fill.
activeDot	boolean | { r?: number; shape?: "circle" | "square" | "diamond" | "commit"; colorByRow?: boolean; nameKey?: string; hollow?: boolean }	true	The markers on every series at the active point.
connectNulls	boolean	false	Draw across missing values instead of breaking the line.
categoryAxis	boolean | { tickFormatter?: (value, index) => string; tickLine?: boolean; axisLine?: boolean; tickMargin?: number; tickCount?: number; domain?: [number | "auto" | "dataMin" | "dataMax", ...]; size?: number; showAll?: boolean; minTickGap?: number; orientation?: "left" | "right" | "top" | "bottom"; series?: string[]; key?: string; hide?: boolean; reversed?: boolean; angle?: number; label?: string | { value, offset? }; unit?: string; ticks?: (number | string)[]; allowDecimals?: boolean; allowDataOverflow?: boolean; niceTicks?: "auto" | "none"; interval?: number | "preserveEnd" | "preserveStart" | "preserveStartEnd" | "equidistantPreserveStart"; padding?: { left?, right?, top?, bottom? }; scale?: "linear" | "log" | "sqrt"; type?: "category" | "number"; mirror?: boolean; tickSize?: number; tick?: boolean; includeHidden?: boolean; allowDuplicatedCategory?: boolean } | AxisOptions[]	true	The category axis. A list draws several, such as a second on top showing another field (key, orientation). Options: reversed, angle, label, interval, padding, type number, tickSize, tick, allowDuplicatedCategory.
valueAxis	boolean | { tickFormatter?: (value, index) => string; tickLine?: boolean; axisLine?: boolean; tickMargin?: number; tickCount?: number; domain?: [number | "auto" | "dataMin" | "dataMax", ...]; size?: number; showAll?: boolean; minTickGap?: number; orientation?: "left" | "right" | "top" | "bottom"; series?: string[]; key?: string; hide?: boolean; reversed?: boolean; angle?: number; label?: string | { value, offset? }; unit?: string; ticks?: (number | string)[]; allowDecimals?: boolean; allowDataOverflow?: boolean; niceTicks?: "auto" | "none"; interval?: number | "preserveEnd" | "preserveStart" | "preserveStartEnd" | "equidistantPreserveStart"; padding?: { left?, right?, top?, bottom? }; scale?: "linear" | "log" | "sqrt"; type?: "category" | "number"; mirror?: boolean; tickSize?: number; tick?: boolean; includeHidden?: boolean; allowDuplicatedCategory?: boolean } | AxisOptions[]	false	The value axis. domain and tickCount shape its scale; a list adds axes, each scaling the series it names, on the right with orientation. Options: reversed, unit, ticks, allowDecimals, allowDataOverflow, niceTicks, scale (linear, log, sqrt), mirror, label, includeHidden.
grid	boolean | { horizontal?: boolean; vertical?: boolean; strokeDasharray?: string; fill?: string; fillOpacity?: number; horizontalFill?: string[]; verticalFill?: string[]; horizontalValues?: (number | string)[]; verticalValues?: (number | string)[]; horizontalPoints?: number[]; verticalPoints?: number[]; horizontalCoordinatesGenerator?: (plot) => number[]; verticalCoordinatesGenerator?: (plot) => number[]; syncWithTicks?: boolean }	true	The grid: horizontal lines at the value ticks by default, vertical on request; dashed lines, a background fill and stripes between the lines; lines at given values or pixels; syncWithTicks keeps the category lines to the ticks that show.
labels	boolean | LabelOptions | LabelOptions[] (LabelOptions: { position?, key?, series?, formatter?: (value, row) => string, offset?, color?, class? })	false	A value or another field above (or below) each point.
tooltip	boolean | { indicator?: "dot" | "line" | "dashed"; hideLabel?: boolean; hideIndicator?: boolean; color?: string; labelKey?: string; nameKey?: string; labelFormatter?: (label, row) => string; formatter?: (value, key, row) => string; footer?: (row) => string; footerLabel?: string; unit?: string; defaultIndex?: number; cursor?: boolean; filterNull?: boolean; trigger?: "hover" | "click"; active?: boolean; position?: { x?, y? }; reverseDirection?: { x?, y? }; itemSorter?: "name" | "value" | "key" | (item) => number | string; includeHidden?: boolean; animationDuration?: number; animationEasing?: string | (t) => number; isAnimationActive?: boolean }	true	The tooltip: false turns it off; an object sets the indicator, hides the heading or swatches, takes names and headings from other keys, formats them, adds a footer line, or turns off the hover cursor. More options: trigger click (a click shows it and it stays), active (always or never shown), position (a fixed spot), reverseDirection, itemSorter and includeHidden.
legend	boolean | { position?: "top" | "bottom" | "left" | "right" | "center" | "insideTop" | "insideBottom" | "insideLeft" | "insideRight" | "insideTopLeft" | "insideTopRight" | "insideBottomLeft" | "insideBottomRight" | { x, y }; offset?: number; iconSize?: number; verticalAlign?: "top" | "middle" | "bottom"; align?: "left" | "center" | "right"; layout?: "horizontal" | "vertical"; iconType?: "square" | "rect" | "circle" | "line" | "plainline" | "diamond" | "triangle" | "cross" | "star" | "wye" | "none"; formatter?: (name, key) => string; itemSorter?: "name" | "key" | (item) => number | string; hideIcon?: boolean; nameKey?: string; toggle?: boolean }	false	The legend: above or below the plot, or beside it with verticalAlign middle; position puts it beside the plot, over it at an inside spot or the center, or at a point, offset moves it, iconSize sizes the swatch; align, a vertical layout, the swatch shape (iconType), a name formatter and an itemSorter; names from another key; toggle makes each item a button that hides its series.
margin	{ top?, right?, bottom?, left? }	{}	Space around the plot in px; each side defaults to 5.
active	number (two-way)	-1	The active item index. Hover and the arrow keys move it; when the pointer leaves it returns to the value it had.
hidden	string[] (two-way)	[]	Series keys not drawn. They stay in the legend, where a toggle legend shows them again.
label	string	"Line chart"	The chart's accessible name and its table's caption.
animate	boolean	true	Marks enter with motion and move to new values. Off under prefers-reduced-motion.
animation	{ begin?: number; duration?: number; easing?: string | (t) => number; matchBy?: "index" | "append" | (item, index) => key; interpolate?: (items, t) => items; newValues?: boolean }	{}	Times the entry and the move to new data. matchBy pairs old and new items by position or by a key, matchByDataKey(field) from the chart package; interpolate draws every frame of a change from the paired items and the eased time; newValues false shows an unpaired new point at once.
showTable	boolean	false	Show the chart's data table under the plot. The table is always in the accessibility tree.
class	string	""	Classes on the figure. Size the chart here: it keeps a 16:9 box unless given a height or aspect-ratio.
attrs	Record<string, string | number | boolean | undefined>	{}	Any other attributes for the figure: id, data-testid, aria-*.
syncId	string	""	Charts with the same syncId share the active item and its tooltip.
syncMethod	"index" | "value"	"index"	Match the shared item by position, or by its category or name.
onActiveChange	(index: number) => void	() => {}	The user moved the active item (hover, leave or keys).
onItemClick	(index: number) => void	() => {}	A click or tap on an item, with its index.
onHiddenChange	(hidden: string[]) => void	() => {}	A legend toggle changed hidden.

Keyboard

Keys	Action
Tab	Focuses the chart (one tab stop) and shows the tooltip for the item the keys last reached, else the active item, else the first.
ArrowRight / ArrowDown	Next item. The same under dir=rtl: the plot is not mirrored, so keys follow the screen.
ArrowLeft / ArrowUp	Previous item.
Home / End	First and last item.
Escape	Hides the tooltip. In a dialog, the dialog stays open until the next Escape.

Data attributes

Attribute	Values	On
data-chart	"bar" | "line" | "area" | "pie" | "radar" | "radial"	figure
data-state	"open" | "closed"	.chart-tooltip
data-index	the item index	.chart-hit and pie, radial marks
data-series	the series key	marks
data-resizing	present while the chart redraws for a new size	figure
data-entered	present once the entry motion is over	figure
aria-pressed	true | false	.chart-legend-item (toggle)

Accessibility

• The plot is one tab stop: role=group, aria-roledescription=chart, named by label, described by the data table.
• The SVG is aria-hidden; a screen reader gets the data from the table, which every chart renders.
• Arrow keys move through the items and each move is announced in a polite live region, for example "February: Desktop 305, Mobile 200".
• Identity is never color alone: a legend for two or more series and labels on the tooltip rows.
• Legend toggles are buttons with aria-pressed.

See also

• Chart (opens in a new tab): What every chart shares: the config and its colors, the tooltip, the legend, the palette and the data table.
• BarChart (opens in a new tab): Vertical, horizontal, stacked and grouped bars with tooltip, legend and labels.
• AreaChart (opens in a new tab): Filled areas, stacked or expanded, solid or gradient, with a crosshair tooltip.
• PieChart (opens in a new tab): Pie and donut charts with labels, a center value, an active slice and stacked rings.
• RadarChart (opens in a new tab): Values on radial axes, one polygon per series, over a polygon or circle grid.
• RadialChart (opens in a new tab): Radial bars and gauges, with tracks, labels along the arc and a center value.