The Perfect Venn Diagram

relative size of set B

1

compute overlap size relative to this set

A

B

overlap relative to set A

0.5

overlap relative to set B

0.5

A Venn diagram is commonly used to depict the relationship among sets. It is difficult, however, to draw freehand a Venn diagram that accurately captures a relationship between the cardinality of the sets and their area of overlap. This Demonstration produces the "perfect" Venn diagram for two sets

A

and

B

where you set the cardinality ratio between the two sets and the area of overlap between them. You can choose whether to compute the area of overlap relative to

A

or to

B

.