A bubble-based heat map is a variation of a heat map where values are represented by circles instead of colored cells in a grid. Each circle’s area is proportional to the numeric value it represents, similar to a proportional area chart (circle). The circles are typically arranged in a grid or matrix, allowing for clear visual comparison across categories or variables. While some versions may also use color to encode an additional measure, the size of the circle remains the primary indicator of value. This visualization helps reveal patterns, relationships, and comparisons in a compact and visually intuitive way.