Intersection() function Python

Last Updated : 18 Apr, 2026

The set.intersection() method in Python returns a new set containing only the elements that are common to all given sets. It compares two or more sets and keeps only shared values. The original sets remain unchanged.

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Intersection of two sets

Example: In this example, common elements between two sets are found using intersection().

Python 
a = {1, 2, 3}
b = {2, 3}
print(a.intersection(b))

Output
{2, 3}

Explanation: a.intersection(b) returns elements present in both sets, only 2 and 3 are common.

Syntax

set1.intersection(set2, set3, ...)

  • Parameters: One or more sets to compare. If no argument is given, it returns a copy of the original set.
  • Return Value: Returns a new set containing common elements.

Examples

Example 1: In this example, the intersection of two and three sets is calculated.

Python 
a = {2, 4, 5, 6}
b = {4, 6, 7, 8}
c = {4, 6, 8}

print(a.intersection(b))
print(a.intersection(b, c))

Output
{4, 6}
{4, 6}

Explanation:

  • a.intersection(b) returns common elements of a and b.
  • a.intersection(b, c) returns elements common to all three sets.

Example 2: Here, the & operator is used as a shortcut for intersection.

Python 
a = {2, 4, 5, 6}
b = {4, 6, 7, 8}
c = {1, 0, 12}

print(a & b)
print(a & c)
print(a & b & c)

Output
{4, 6}
set()
set()

Explanation:

  • a & b returns common elements of both sets.
  • a & c returns set() because no elements match.
  • a & b & c returns common elements among all three sets.

Example 3: In this example, intersection() is compared with symmetric_difference().

Python 
a = {2, 4, 5, 6}
b = {4, 6, 7, 8}
print(a.intersection(b))
print(a.symmetric_difference(b))

Output
{4, 6}
{2, 5, 7, 8}

Explanation:

  • a.intersection(b) returns common elements.
  • a.symmetric_difference(b) returns elements not common in both sets.
  • Intersection keeps shared values, while symmetric difference keeps non-shared values.
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