A Venn diagram uses overlapping circles to show the relationships between sets. Items in the overlap belong to more than one set; items outside the overlaps belong to only one. The size of each circle and the size of the overlapping region can be adjusted to reflect the relative quantities.

Venn diagrams are a natural tool for comparing any two or three groups that share members: skills that two roles have in common, topics covered by multiple books, or qualities shared between different travel destinations.

This diagram type is experimental and requires Mermaid v11.12 or later.

venn-beta
    title "Skills for a Content Creator"
    set Writing["Writing"]:30
        text w1["Long-form articles"]
        text w2["Copywriting"]
        text w3["Editing"]
    set Visual["Visual"]:25
        text v1["Photography"]
        text v2["Graphic design"]
    union Writing,Visual["Both"]:10
        text wv1["Social captions"]
        text wv2["Newsletter design"]

Sets are declared with set; overlapping regions are declared with union. The :n suffix sets the relative size of each circle or overlap. Text items placed inside a set or union appear as labels within that region.