Charts

TwMatrixChart

TwMatrixChart is a Blazor matrix chart: a grid with a dot sized by value where a row and a column meet, for two categorical dimensions.

Last updated 18 October 2026

Please be aware this component is new, may have bugs and/or be subject to change. Please report any bugs at https://github.com/twblazor/twblazor/issues.

Basic usage

TwMatrixChart lays each series out as a row and each category as a column, and draws a dot where they meet, sized by the value. The area of the dot, not its width, follows the value.

Support tickets by day and shift

RAZOR

<TwChart Title="Support tickets by day and shift">
    <TwMatrixChart Categories="@_days" Series="@_shifts" />
</TwChart>

CSHARP

@code {
    private readonly string[] _days = ["Mon", "Tue", "Wed", "Thu", "Fri"];
    
    private readonly ChartSeries[] _shifts =
    [
        new("Morning", [34, 28, 31, 25, 40]),
        new("Afternoon", [52, 47, 58, 49, 61]),
        new("Evening", [18, 22, 15, 27, 33])
    ];
}

Labels

ValueLabel names the value in tooltips and CategoryHeader names the first column of the table view.

Support tickets by day and shift

RAZOR

<TwChart Title="Support tickets by day and shift">
    <TwMatrixChart Categories="@_days" Series="@_shifts" ValueLabel="Tickets" CategoryHeader="Day" />
</TwChart>

When to use

Dot sizes are harder to compare than shades when values are close together. For a dense grid, or to print the values, use TwHeatmapChart.

Summary

Tooltips and the table view give the value of every series for each category.

Shared features

The legend, tooltips, keyboard navigation, table view, value formatting, height and empty state work the same on every chart. See TwChart for those options.

The plot is a single Tab stop. Each data point is announced with its series and value as focus reaches it, and the table view presents the same data without the plot.

Key	What it does
`Tab`	Moves focus into the plot, onto the data point last visited.
`Arrow Right` or `Arrow Down`	Moves to the next data point.
`Arrow Left` or `Arrow Up`	Moves to the previous data point.
`Home` or `End`	Moves to the first or last data point.
`Escape`	Hides the tooltip of the focused data point.
`Enter` or `Space`	On a legend item: shows or hides that series. On the table button: switches between the chart and its data table.