Definition
A variable-width stacked bar chart where both column width and column height carry data: column width represents market segment size, column height represents composition or share, and rectangle area represents absolute contribution, answering in one chart 'how big the market is, what the structure is, and where we stand.'
In detail
A Mekko chart is not strategic planning itself, but a quantitative visualization tool commonly used in strategic planning, market segmentation, and business portfolio analysis. In a standard stacked bar chart, each column is of equal width, allowing only proportional comparison; a Mekko chart makes column width another data dimension, thus enabling simultaneous comparison of market segment sizes and internal structures. When reading, sequentially confirm what the horizontal width, vertical percentage, and rectangle area represent, and verify the reporting period, units, and data sources. It should not be used when categories overlap, widths lack a unified measurement basis, or there are too many samples, as the area can create misleading intuition.
Example in practice
When a company decides which market segments to invest in next, it can set each column width to the market's sales or serviceable addressable market, and the column height to brand share, customer type, or product mix proportion. The team first looks at which markets are large enough, then examines its own share and competitive structure, identifies opportunities such as 'large scale but low share' or 'small scale but high profit,' and then forms strategic choices by combining growth rate, profitability, and capability thresholds; the Mekko chart provides a factual baseline but does not replace final decision-making.