What is the difference A−B?

The elements of A that are not in B. A−B and B−A are generally different, so both are listed.

What is the symmetric difference?

A △ B holds the elements in exactly one of the sets: (A−B) ∪ (B−A), equivalently the union minus the intersection.

Why are there fewer elements than I typed?

Sets contain no duplicates, so repeated entries are merged — the tool tells you how many were removed.

What does the Jaccard similarity mean?

The size of the intersection divided by the size of the union, from 0 to 1. It measures how similar two sets are and is widely used in text and data deduplication.

🔵

🔵Set Calculator - Union, Intersection, Difference and Symmetric Difference

Paste two groups of elements — numbers or words — to get the union, intersection, A−B, B−A and the symmetric difference, together with subset, superset, equality and disjoint checks, the Jaccard similarity, the power set size and the size of the Cartesian product. Duplicates are removed automatically.

Free · No sign-up · Runs in your browserLast updated: 2026-10-26

Loading tool...

How to use Set Operations

1Enter the elements of set A and set B in the two boxes
2Separate elements with spaces, commas or line breaks
3Read the results and choose whether to sort them numerically

FAQ

What is the difference A−B?: The elements of A that are not in B. A−B and B−A are generally different, so both are listed.
What is the symmetric difference?: A △ B holds the elements in exactly one of the sets: (A−B) ∪ (B−A), equivalently the union minus the intersection.
Why are there fewer elements than I typed?: Sets contain no duplicates, so repeated entries are merged — the tool tells you how many were removed.
What does the Jaccard similarity mean?: The size of the intersection divided by the size of the union, from 0 to 1. It measures how similar two sets are and is widely used in text and data deduplication.