Johan de Groot

Responsive Labels – Smarter, Cleaner Dashboards

Johan de Groot · 22 May 2025 ·

Data Visualization is about visualizing data the right way.

Interactive business dashboards tend to have a special challenge: the must display data with accurate labels, regardless of how the data changes from day to day. Many infographics visualizations are using static data – and therefor the labels can be put on the most convenient location. But what happens when the data changes – either due to new data, or filtering? Labels will overlap, disappear, and/or get mixed up.

The funnel chart is one type of visualization that’s especially prone to this, even with just a few data marks. While working on one, I came up with a solution to keep all the labels nice and clear, no matter what the data throws at it. Bonus: it’s flexible enough for easy customization!

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Area Funnel chart in Tableau: Visualizing the Drop-Off

Johan de Groot · 15 May 2025 ·

In the world of digital analytics and customer journeys, not every user makes it to the finish line. Some browse a product, others add it to their cart, but only a fraction complete a purchase. Understanding where users drop off—and how many—can offer crucial insights for optimizing your process. That’s where funnel visualizations come in.

Funnel charts are a powerful way to illustrate step-by-step attrition across a defined process. Whether you’re tracking sales, onboarding, or lead conversions, a funnel view can make complex user behavior immediately digestible. Each stage visually narrows to reflect fewer participants, highlighting friction points and conversion opportunities.

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Change marks on Hover

Johan de Groot · 8 May 2025 ·

Sometime you want to make a dramatic statement – and sometimes you just need a little nudge to help users understand a dashboard.

Tableau makes it really easy to create a minimalist dashboard – and tooltips are a great way to unlock the data behind a mark. Emphasizing the datapoint of the tooltip will make the visualization just a little better. And this is even more important on charts with multiple lines.

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Animated icons in Tableau

Johan de Groot · 1 May 2025 ·

An old but very efficient way to point the attention to a row in a table is to add a small text-based icon in front of it. A subtle dot in front of a bar can help you tell the story of data.
But you might want to use less-subtle ways to highlight data?

Animation is such a way – and can even add some more fun to a dashboard. In Tableau, this is really easy to accomplish using Image Roles.

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API to Tableau, the Smart Way: A Guide to Table Extensions

Johan de Groot · 10 April 2025 ·

Getting data from external APIs into Tableau often involves several workarounds —manual extracts, middle-ware scripts, or writing to a database. This isn’t bad per se, but if you just want real time data from an API, Table Extensions are a clean and direct solution.

Table Extensions allow you to connect Tableau directly to external data sources like APIs using Python, R, or other analytics engines. This means you can fetch live data—whether it’s weather updates, currency exchange rates, or stock prices—and use it as if it were a regular data source in Tableau.

In this post, I’ll walk you through how to set up your first Table Extension, use Python to pull live data (without storing anything), and explore the benefits and best practices of using this approach—especially when working with real-time or short-lived data.

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