Set operations (intersection, union, difference, complement) are easier to see than to define. This page shows each one in plain words, with a small diagram and an example you can open in the tool. It also has a counts-only classroom exercise and made-up examples for class. Everything runs in the browser: no account, no upload.
Venn diagram maker from lists
Paste one list per set into its box, or drop a file, and the diagram is drawn at once: a Venn diagram for 2 to 6 sets, an UpSet plot for up to 16. Click a region to see its items. Students can make a diagram from their own lists in a few minutes, and save it as PNG, SVG or PDF for a handout.
Set operations examples
Each set operation is a question about which items are in which sets. The Ask box answers it in the tool. The examples use the made-up students in three courses (Maths, Biology and Art).
Intersection: what the sets share
The intersection of two sets holds the items that are in both. In a Venn diagram it is the middle, where the circles overlap. Read it as "and".
Ask box: Maths and Biology
Union: everything in either set
The union of two sets holds every item that is in at least one of them, counted once. In a diagram it is both circles together. Read it as "or".
Ask box: Maths or Biology
Difference: in one set but not the other
The difference "A not B" holds the items of A that are not in B: the part of A outside the overlap. Students often mix it up with "B not A", so ask about both.
Ask box: Maths, not Biology
Complement: everything outside a set
The complement of a set holds the items that are not in it. InteractiVenn only knows the items in your lists, so the complement means: the items that appear in some list but not in this set.
Ask box: not Art
Classroom exercise: counts only
Students predict a diagram from numbers alone, with no lists. Counts are enough: how many items sit in each region. The File menu item "Type region counts only" takes two to four sets.
- Write the counts for three sets on the board: one number for each region, for example 6 students in Maths only, and 1 in all three courses.
- Ask the class to work out from the numbers alone: how many take Maths and Biology, how many take Biology or Art, how many take Maths but not Art.
- Open File ▾ and choose "Type region counts only…". Type the same numbers, region by region.
- The diagram is drawn from the counts. Compare it with the class answers. To check a whole set, open "Students in three courses" from File ▾ › Examples: 21 students in all.
With counts only there are no names to click. Each item must belong to exactly one region, so the counts must add up to the number of items you mean.
Everyday examples for class
All made up, so no real person, product or paper is named. Each example opens from its button and is also in File ▾ › Examples.
Students in three courses
Which students take Maths, Biology or Art. Good for "and", "or" and "not" in the Ask box.
Three reading lists
Which books are on the term list, the summer list or the book club list. Good for asking which items several lists share.
A note for teachers
Nothing you type or load is sent anywhere. The lists stay in the browser tab. There is no account, no login and no copy of your data on a server. When you close the tab, the work is gone unless you saved it.
To keep a lesson, use File ▾ › Save session (a .interactivenn file) and open it again later. Saving preferences is optional and off by default.
It runs in any modern browser on a laptop, tablet or phone, with no installation. Students can use the same page at home.