Description

D3 chart components offer various chart types and tools for data visualization.

Refer to Charts showcase, to explore all charts and pick the best one for your needs.

Grid and axes

Axes help users understand data relationships and navigate through data. A plot can include horizontal and vertical lines.

Grid and axes

Grid lines	Appearance example	When to use
Horizontal lines		Use with charts showing data trends over time.
Both horizontal and vertical lines		Use with scatter plots and bubble charts.
Vertical lines		Use with horizontal bar charts.

Basic styles for Chart.Plot:

• The Y-axis is hidden by default.
• Additional axes are colored with --chart-grid-line token.
• X-axis and additional active lines on the grid (if needed) have --chart-grid-x-axis color.

TIP

Keep additional lines dim to focus on data.

Margins

• Y-axis values have 16px left and right margins.
• X-axis values have a 12px top margin.

Reference line

You can show different reference lines (highlight date or dates range) to guide user through your data visualization.

Minimum and maximum axes' number

Use 3-5 horizontal additional horizontal lines for clarity. Use rounded values on axes, for example, 25K, 20K, 15K, 10K.

TIP

The recommended minimum chart height is 120px. For such a chart, it's advisable to display 3 additional horizontal guides. Keep in mind that small charts might make it hard to see data changes.

It's recommended for smal charts having no more than 3 horizontal lines.

The maximum chart height depends on your specific case. For charts with greater heights, use no more than 5-6 additional horizontal lines.

Tooltip

Tooltips show data when hovering over chart parts, even if no data is present (use "n/a" in this case).

The tooltip aligns with the cursor with a 4px margin within the chart area.

• It shows data for all lines for a selected date.
• Align tooltip values to the right for easy comparison.
• Include total values in the tooltip.
• Synchronize tooltips across charts for data comparison.

TIP

Avoid measurement units in tooltips unless needed for clarity. However, in more complex charts, such as scatterplots, adding a measurement unit can enhance data reading.

Tooltip styles

Tooltip padding is always 12px.

Unavailable data

Represent missing data with a dashed line.

Start of data collecting

Use a solid line for new data. The tooltip should mention the start of data collection, use --chart-grid-y-accent-hover-line token for the text color.

Dots

Chart dot styles

Appearance	Styles
	Default dot size is 8px * 8px. The dot's size in hovered state is 10px * 10px.
	Color for the additional vertical line that appears on line charts when hovering is --chart-grid-y-accent-hover-line.
	Background color for hovering bar charts is --chart-grid-bar-chart-hover.

Legend

Legend explains chart data and can act as filters. For detailed information, refer to Chart legend.

Usage with Card

In our design system, data is typically placed within a Card, which consists of Card.Header and Card.Body.

Chart title

Make sure each chart has a title, and it's clear which chart each title belongs to.

If you're displaying the chart inside a Card, use the Card.Title component.

Chart description

You can add a description text to your chart. Typically, such a text can provide information on maximum/minimum data statuses, explains the data source, or offers insightful advice related to visualized data.

If you're displaying the chart inside a Card, use the Card.Description component.

Initial data loading

During the initial data loading, display the Skeleton instead of the chart.

If the chart has a title, it should be displayed during the initial loading. The user should be aware of what's being loaded, and whether they need to wait for the process to complete.

TIP

Each chart type has a specific skeleton. Refer to specific chart type guides and Chart Skeleton examples.

Edge cases

Edge cases vary by chart type. Check the specific chart documentation for details. For empty states, refer to Error & n/a widget states.