New: Dual-axis charts in Datawrapper

Dual-axis charts let you compare two metrics in a single chart, even when they cover vastly different y-axis ranges — like 0–100% and 150,000–200,000 units sold. They’re great for comparing growth over time: when one metric goes up, what happens to the other?

Because they’re easily misread, dual-axis charts are usually not the best choice for general audiences. For certain industries, though, they're an essential tool. And as more people from different industries and verticals began using Datawrapper, we've seen the need for more specialized visualization types. So today, we’re making it possible to create dual-axis charts with our all-new Business plan.

Quickly combine bars, lines, and areas

However you want to display your data, you’ll have it set up in moments. Drag and drop your metrics to assign them to the left or right axis, then choose the chart type to show them in. You can build the classic column-and-line combo chart, but also combinations of lines and lines, (stacked) areas and lines, and even grouped or stacked columns and lines.

To draw your readers’ attention to your most important metrics, you can style each chart type — like the colors, width and dashes of your lines, the gap between columns, and the opacity of areas.

Make your scales obvious with color keys

In dual-axis charts, it should be very easy to see which scale each metric uses. That’s why we put a lot of thought into designing different color key layouts, so you can find one that fits your data:

You can also add axis titles on each side to better group and explain related data series:

To make the connection between metric and scale even clearer, you can make the color keys interactive. When you do, readers can hover over or tap them to highlight the related metrics and vertical axes. The grid labels can also take on the color of the associated data series. (Too much? Just turn it off.)

Label values, using our smart algorithms

Labels that sit directly on data points can make dual-axis charts less misleading: readers see immediately that “125 mm” and “29 °C” can’t be compared. In Datawrapper dual-axis charts, you can add value labels to lines and columns:

Our smart algorithm hides overlapping labels and automatically adjusts the label style to keep them readable and high-contrast enough to meet accessibility standards.

Add context with annotations

For more custom labels, dual-axis charts support Datawrapper’s best-in-class annotations, allowing you to call out interesting trends and provide context to readers. You can associate each annotation to the left or right axis to have it stay in the right place if the scale changes and have it take on the color of its associated series.

Show readers the underlying data with tooltips

Dual-axis charts are all about revealing general trends. But the exact values are only a hover away: by default, interactive tooltips let readers move their mouse (or finger!) across the chart to compare values, shown in a clear table layout with helpful reference symbols.

Keep scales comparable

A common issue with two axes is mismatched scales that create misleading correlations. To avoid this, we’ve built the following behavior into our dual-axis charts:

• If one vertical axis starts at zero, the other will too (unless it’s really far from zero).
• If one vertical axis shows data that goes below zero, the other axis’s baseline is adjusted so they are aligned.
• Column and area charts always include zero, just as they do in our regular versions of those chart types.
• When the lines on both axes are “floating” — meaning zero baselines wouldn’t be useful — we offer an option to align the axis scales. This makes the lines comparable, as in an indexed chart.

Use automatic scales, or go custom

By default, the two vertical grids have independent tick intervals. For a cleaner look, you can choose to align them, and the built-in algorithm will adjust the scales automatically.

You can also configure your scales manually by setting custom ranges, tick values, and grid design elements — or turn them off altogether. It's your choice.

Everything else you’re used to

We’ve pointed out a lot of special dual-axis chart features here that will help your readers understand them correctly: color key options, colored grid labels, value labels, tooltips, and aligned axis scales.

But all other Datawrapper features you’re used to work with dual-axis charts, too: dark mode; PNG, SVG, and PDF export; responsive mobile support; automatic descriptions for screen readers and keyboard controls for interactive elements; multilingual support, including right-to-left languages; and custom themes.

Get started with dual-axis charts

To try out the new Datawrapper dual-axis charts — even if you’re not on the Business plan — hover over any of the examples in this article and click “Edit this chart.” You can also open a demo in our chart type selector, directly in Datawrapper.

To learn more about this special chart type, we’d also like to invite you to:

• sign up for one of our webinars on August 20 or September 16, where we demo both a dual-axis chart and a waterfall chart;
• find out how to create your first dual-axis chart in our Academy; and
• read our new dos and don’ts guide to dual-axis charts on our blog.

Thanks to everyone who worked on this feature: Luc Guillemot (project lead), Moritz Kuhn (lead designer), Elliot Bentley, Ivan Lokhov, Alexander Käßner, David Wendler, and Elana Levin Schtulberg.

We hope you enjoy creating dual-axis charts in Datawrapper. If you have any questions or feedback, don’t hesitate to reach out to our team at support@datawrapper.de.