This entry is part of the Chart Index, the reference library for the Chart Design Field Guide.
The Marimekko chart — named after the Finnish textile designer Marimekko, in homage to its grid-like geometry — is a stacked bar with a twist: every bar's width is also data. Where a standard stacked bar uses uniform bar widths, the Marimekko makes width proportional to one quantitative variable and stack height proportional to another. The result is a grid of rectangles where each cell's area is a meaningful product of two variables.
It is the chart used in strategy consulting decks since the 1970s, often for market share by segment × revenue size. The form is dense, information-rich, and — for the right question — uniquely communicative. For most others, it is a way to make two simpler charts confusing simultaneously.
What it is
A Marimekko chart maps a primary categorical variable to bar position along the x-axis, a secondary categorical variable to colour-coded segments within each bar, the bar's height to the share of the segment within the bar (typically 0–100%), and the bar's width to a third quantitative variable (the bar's total size). Each cell's area thus represents segment value within its category × category size.
Six industry verticals across the x-axis (width proportional to total spend), each partitioned into four workload types (height proportional to share within industry). The cell areas show absolute workload spend per industry; the bar widths show industry size; the stack heights show workload mix.
When to use it
Marimekko charts are the right choice when:
- You have a two-categorical, two-quantitative dataset where both quantitative dimensions matter.
- The reader's question is "how big is each cell, in context of both dimensions?"
- The form is a strategic or planning deliverable — market sizing, portfolio review.
- You have a small enough matrix (3–8 categories × 2–5 segments) for cells to be readable.
- The audience is familiar with the form or willing to read its legend carefully.
When not to use it
- Most business communication. The form's complexity demands attention; for executive summaries, a stacked bar or pair of bars usually wins.
- More than 8 categories. Bar widths shrink to ribbons; cells become unreadable.
- More than 5 segments per bar. The stack becomes a tower of colour bands.
- When width does not have a meaningful encoding. A Marimekko with uniform widths is just a 100% stacked bar — use that instead.
Design principles
Sort widths by size
The widest bar should be leftmost (or rightmost, consistently); progressing in decreasing width gives the chart visual rhythm and helps the eye anchor on the major categories first. Random width ordering produces a wall of irregular columns.
Order segments consistently
Every bar must stack its segments in the same order. The reader builds a mental template — bottom is Cloud, then Data, then Identity — and applies it across bars. Re-ordering by segment value per bar destroys comparability.
Use one colour family for segments
Stacked segments share an axis of meaning. A single sequential hue family (light to dark) lets the reader compare segment-by-segment across bars. Saturated rainbow palettes turn the chart into a quilt.
Label totals on the x-axis
Below each bar, place the category's total value or label. Above each bar (or alongside), the segment percentages. The chart's two encodings each need a clear annotation channel; mixing them confuses.
Add a thin top axis for width
The x-axis is not a category axis in the traditional sense — bar positions are proportional to widths. A short axis showing 0%, 25%, 50%, 75%, 100% along the top helps the reader read bar widths as shares of the total.
Avoid 100% Marimekko when you mean stacked bars
If your bars all have the same total width (i.e., you are normalising to 100%), you have a 100% stacked bar chart, not a Marimekko. The Marimekko's information density is in the variable widths.
Resist the urge to chart everything in one
The form's danger is that it can encode three or four dimensions in one chart. Just because you can does not mean you should. If the reading task does not need the area = product interpretation, use two simpler charts.
Anatomy
A Marimekko's anatomy is variable-width stacked bars laid out with both axes encoded. The chart is dense by design; the design challenge is to ensure each cell is readable in isolation and the matrix is readable as a whole.
Related types
- Mosaic plot — the statistician's name for the same form, used for contingency tables in categorical analysis.
- 100% stacked bar — uniform widths, normalised heights. The Marimekko's simpler cousin.
- Treemap — for area-encoded part-to-whole without the cross-tabulation structure.
- Sankey diagram — for flows between two categorical dimensions.
- Heatmap — for the same matrix structure with magnitude encoded as colour instead of area.
Reading list
- Hartigan, J. & Kleiner, B. (1981). Mosaics for Contingency Tables. The original statistical mosaic plot.
- Friendly, M. (1994). Mosaic Displays for Multi-Way Contingency Tables. The modern extension.
- Tufte, E. (1990). Envisioning Information. On variable-width bar variants.