In the world of data visualisation, the Mekko chart stands out as a versatile and insightful tool. Also known as the Marimekko chart in some circles, this dynamic visualisation blends the concepts of market share, category size and distribution into a single, readable graphic. If you want to compare segments across multiple categories while preserving the relative importance of each segment, the mekko chart is often the best choice. This guide demystifies the Mekko chart, explains when and how to use it, and offers practical tips for designing clear and compelling visuals that perform well in search results and in presentation rooms alike.
What is a Mekko Chart and How Does It Work?
The mekko chart is a two-dimensional visualisation that combines horizontal and vertical scaling to convey two kinds of information simultaneously. Each column represents a primary category, with the width of the column proportional to the category’s overall size. Inside each column, the stacked segments show the composition of that category, with the height of each segment proportional to its value within the category. The result is a mosaic of differently sized blocks that enables quick comparisons of both category size and internal mix across categories.
In practice, a Mekko chart helps answer questions such as: Which region contributes most to overall sales, and how do product lines perform within that region? How does the market share of different channels vary across geographies? The visual design makes it easier to spot dominant categories, shifting trends and outliers at a glance—something that can be harder to capture with separate bar charts or pie charts.
A Brief History: From Marimekko to Mekko Chart
The Mekko chart has its origin in the work of Marimekko OY, a Finnish design company known for its bold fabrics and graphic layouts. In data visualisation circles, the term Marimekko is often used to acknowledge the inspiration behind the approach. Over time, analysts adopted the nomenclature “Mekko chart” to reflect the chart’s distinctive structure—wide categories on the x-axis and variable-height blocks within each category—while still recognising the chart’s roots in Marimekko’s visual philosophy. Today, both terms are understood in business intelligence, but the capitalised format Mekko Chart is commonly used when referring to the model itself or as a formal chart type in software documentation.
Key Uses for the Mekko Chart
Knowing when to use a mekko chart is essential to getting actionable insights. This visualisation is particularly strong in contexts where you need to:
- Display market share by segment across multiple regions or categories, while preserving the relative size of each region.
- Illustrate product mix or portfolio composition across different business units, with a clear sense of scale for each unit.
- Compare revenue or profit contributions by segment within and across geographies, showing both distribution and scale in a single view.
- Show demand by channel within countries or cities, helping to prioritise resource allocation based on combined size and composition.
Compared with a standard stacked bar chart, the mekko chart retains the varying widths of columns, which reflect the importance or size of the primary category. This additional dimension is what makes the Mekko Chart particularly suited to strategic decision-making and executive reporting.
Understanding the Mechanics: Width, Height and Segments
To read a Mekko chart effectively, you should keep three core elements in mind:
- Width of columns represents the overall size or weight of the primary category (for example, regional sales or market share).
- Height of segments within each column indicates the relative value of a subcategory (for example, product lines within a region).
- Colour or pattern for segments distinguishes different subcategories, enabling quick visual comparison across columns.
This combination means you can answer multifaceted questions at once: which region is largest overall, how each region contributes to its region’s total, and whether the internal mix is shifting over time or differs between regions. The Mekko Chart is especially powerful when the audience needs to understand both scale and composition in a compact visual format.
Data Requirements and Preparation for a Mekko Chart
Before building a Mekko chart, you’ll need structured data that supports both column widths and internal segment heights. A typical data layout looks like this:
- Primary categories (e.g., regions, market segments, product families)
- For each primary category, subcategories (e.g., product lines, channels, sub-regions)
- Values representing the size of each primary category and the contribution of each subcategory within that category (e.g., sales, revenue, or units)
Crucially, the total width of all columns should reflect the sum of the primary category values. Within each column, the sum of the subcategory values should equal the corresponding column width. In other words, the chart is a two-layer quantification: horizontal scale for main categories, vertical scale for the internal mix.
When preparing data, consider these tips:
- Ensure data is consistently scaled across all categories to avoid misinterpretation.
- Decide on a measurement base (e.g., currency or units) and apply it uniformly.
- Anticipate the audience’s focus: if you want to stress the largest regions, make sure their column widths are visually dominant.
- Think about time: if you’re showing a trend, you may want a sequence of Mekko charts or an interactive Mekko with a time slider.
Creating a Mekko Chart: A Step-by-Step Tutorial
Many modern data visualisation tools support Mekko charts either built-in or via custom visuals. The following steps provide a practical roadmap for creating a mekko chart in common software environments. The general workflow remains the same whether you use Excel, Tableau, Power BI or another platform.
Excel: Building a Mekko Chart with Workarounds
Excel does not include a native Mekko chart in all versions. However, you can craft a mekko-style visualisation by combining a stacked area approach with a custom data layout and clever formatting. A typical method involves:
- Preparing a data table with a primary category column, a subcategory column, and a value column. Ensure the primary category sums are accurate for column widths.
- Creating a stacked column chart where each column corresponds to a primary category and each segment reflects a subcategory.
- Adjusting the horizontal axis to represent the cumulative width of the columns. This often requires helper columns to compute the category boundaries.
- Applying consistent colours to subcategories across columns and adding data labels for clarity.
While this approach can be meticulous, it yields a flexible mekko chart in Excel without relying on external add-ins. If you frequently build Mekko charts, consider dedicated add-ins or tools that specialise in Marimekko-style visuals for efficiency and consistency.
Power BI and Tableau: Native or Custom Visuals
Power BI and Tableau have strong ecosystems for advanced visuals. In Power BI, you can search the visuals marketplace for “Mekko chart” or “Marimekko chart” and install a custom visual. Tableau users often explore a variety of community-driven or vendor-provided mekko visuals or build a mekko-like dashboard using a combination of calculated fields and dual axes. When choosing a Mekko chart in these environments, keep an eye on:
- Data model compatibility: ensure your data nicely maps to category widths and segment heights.
- Performance: large datasets can slow interactive mekko visuals; consider data reduction or aggregation.
- Accessibility: incorporate labels and tooltips so users can interpret the chart without relying solely on colour.
Design Best Practices for the Mekko Chart
To maximise clarity and impact, follow these design recommendations for the Mekko chart:
- Colour discipline: use a limited, purposeful colour palette. Reserve bold colours to emphasise key segments and use neutrals for the rest to avoid visual clutter.
- Label strategy: keep labels legible. Consider placing only the most important labels on the chart and providing a detailed legend or interactive tooltips for full data access.
- Axis and gridlines: use clean gridlines to aid alignment without distracting from the data blocks. Avoid excessive tick marks on the horizontal axis.
- Aspect and spacing: ensure that columns are visually balanced. Too narrow a column or excessive whitespace can distort perception of size and mix.
- Consistency across visuals: when presenting multiple Mekko charts, maintain the same colour mapping and scale to facilitate comparison.
- Contextual annotations: add concise notes to highlight notable shifts or surprising results. A well-placed annotation helps anchor the viewer’s interpretation.
Common Pitfalls to Avoid in Mekko Chart Usage
Like any powerful visualisation, the Mekko chart can mislead if used poorly. Watch out for these frequent issues:
- Overcrowding: too many categories or subcategories can create a dense chart that is hard to read. Consider grouping small segments into an “Other” category or splitting the chart into multiple visuals.
- Inconsistent scales: mixing currencies or units without proper normalisation can distort comparisons. Keep units consistent within a chart.
- Misreading width as importance only: while width indicates category size, a dominant internal segment can carry significant value; ensure the audience understands both dimensions.
- Ambiguous legends: if colours do not map clearly across all columns, readers will struggle to decode the mix. A clear legend or interactive hover text is essential.
Practical Case Study: A Hypothetical Market Segmentation
Imagine a consumer electronics company that sells devices across three regions: North, Centre and South. Each region ships three product families: Audio, Visual, and Wearables. The Mekko chart allows the business to see at a glance which region drives overall revenue, while also showing how each product family contributes within that region. In the Mekko chart, you would expect the three region columns to differ in width according to regional revenue. Inside the North region column, the height of the Audio, Visual and Wearables blocks reveals the internal revenue mix; similarly for Centre and South. If North has the highest revenue and Wearables are increasingly dominant there, stakeholders can identify where to prioritise inventory, marketing budgets and product development. This single Mekko chart communicates both scale and composition in a way that two separate charts could not achieve efficiently.
Interpreting and Communicating Insights from a Mekko Chart
When presenting a Mekko chart, frame the insights to tell a cohesive story. Start with the big picture: which regions or categories hold the largest share. Then drill into the internal mix: which subcategories contribute to growth or decline within those regions. Use annotations to flag notable shifts, such as “Wearables growing fastest in North” or “Centre region showing a heavy Visual mix.” For executive audiences, pair the Mekko chart with a brief narrative that explains what actions are warranted, such as reallocating marketing spend, prioritising product development, or adjusting regional strategies. The ultimate aim is to translate the visual into concrete decisions that move the business forward.
Mekko Chart Variants and Related Visualisations
While the Mekko chart is a distinct chart type, there are related visualisations that share its philosophy of combining size and composition. The Marimekko visualisation family includes variants that emphasise time, geography or segmentation by multiple layers. Other approaches, such as stacked bar charts or heat maps, can complement a Mekko chart by providing alternative perspectives on the same data, particularly when a limit on chart complexity is required for accessibility or print formats.
Frequently Asked Questions about the Mekko Chart
Below are common questions organisations have when adopting the Mekko chart in reporting and analytics:
- What is a Mekko chart best used for? The mekko chart excels at showing the relative size of categories and the internal mix within each category—perfect for market share analysis, portfolio evaluation and cross-regional comparisons.
- How do I choose the right data for a Mekko chart? Focus on data where the column widths are meaningful and the internal composition matters. Avoid presenting too many micro-segments in a single chart.
- Can a Mekko chart include time? Yes, but it may require an interactive or animated visual to avoid clutter. Time-based Mekko charts can show evolution across periods by sequencing columns or using a time slider.
- Is a Mekko chart difficult to read for non-technical audiences? It can be, if overcomplicated. Use clear legends, annotations and, when appropriate, supplementary charts to aid understanding.
- Does the Mekko chart require special software? Most modern BI tools can produce Mekko charts with built‑in features or via custom visuals. Basic versions are possible in spreadsheet software with careful data preparation.
What the Future Holds for Mekko Chart Visualisations
As organisations accumulate more data, the demand for compact, information-rich visuals grows. The Mekko chart is well positioned to evolve with this trend. With advances in interactive dashboards, it is becoming easier to explore Mekko charts across filters, drill down into subcategories and compare multiple Mekko visuals side by side. Designers are also experimenting with responsive Mekko charts that adapt to screen size, preserving readability on desktops, tablets and mobile devices. In practice, this means more robust insights delivered with greater efficiency and less cognitive load for readers and decision-makers alike.
Conclusion: Why the Mekko Chart Deserves a Place in Your Toolkit
The Mekko chart is a powerful, two-dimensional visualisation that blends size and composition into a single, interpretable diagram. For analysts, marketers and executives seeking to understand how different categories contribute to overall performance, the Mekko chart offers a clear, compact and persuasive way to present data. By carefully preparing data, choosing the right tool, observing design best practices and mindfully interpreting the results, you can unlock valuable insights that may be missed with more conventional charts. Whether you call it a Mekko chart, a Marimekko visualisation or simply a flexible mosaic chart, this approach remains a staple for strategic analytics and compelling business storytelling.