A Venn diagram uses overlapping shapes to show what groups have in common and what belongs only to one group. Each circle represents a set; each overlap represents items that belong to every set touching that region.
For two or three sets, circles make similarities and differences easy to scan. A data-driven maker is more reliable than manually typing counts because it calculates each region from the lists themselves.
With four or more sets, circle layouts often become ambiguous or omit possible intersections. This tool therefore switches to an UpSet-style matrix for 4–6 sets so the result stays mathematically honest.
Sets
Named groups containing concepts, records, genes, products, or other items.
Unique regions
Items that appear in exactly one set and nowhere else.
Intersections
Items shared by a precise combination of two or more sets.
Universe
The combined list of every distinct item supplied across all sets.








