PHP array_intersect() Function: Syntax, Parameters, Return Value, and Practical Examples

In PHP, the array_intersect() function compares two or more arrays and returns a new array containing only the values that exist in all input arrays.

Syntax

array_intersect(array1,array2,array3...)

Parameters

array1 : Required. The base array for comparison.

array2 : Required. An array to compare against array1.

array3, ... : Optional. Additional arrays to compare with array1.

Return Value

The function returns an array containing all values that are present in every input array.

Examples

Example 1:

$array1 = array("apple", "banana", "orange", "grape");
$array2 = array("banana", "mango", "grape");
$result = array_intersect($array1, $array2);
print_r($result);

Output:

Array
(
    [1] => banana
    [3] => grape
)

Example 2:

$array1 = array(1, 2, 3, 4, 5);
$array2 = array(4, 5, 6, 7);
$result = array_intersect($array1, $array2);
print_r($result);

Output:

Array
(
    [3] => 4
    [4] => 5
)

Example 3:

$array1 = array("red", "green", "blue");
$array2 = array("green", "blue", "yellow");
$array3 = array("blue", "yellow", "pink");
$result = array_intersect($array1, $array2, $array3);
print_r($result);

Output:

Array
(
    [1] => green
    [2] => blue
)

Explanation

In Example 1, $array1 contains "apple", "banana", "orange", and "grape" while $array2 contains "banana", "mango", and "grape". The intersected result includes the common values "banana" and "grape".

In Example 2, $array1 holds numbers 1‑5 and $array2 holds 4‑7. The function returns the shared numbers 4 and 5.

In Example 3, three arrays of color strings are compared; the common colors across all three arrays are "green" and "blue".

Summary

The array_intersect() function is a frequently used PHP utility for comparing and extracting common elements from multiple arrays, helping developers handle array‑related logic more efficiently.