count duplicate elements in array php code example

Example 1: get duplicate value from array php

$arr = array(1, 4, 6, 1, 8, 9, 4, 6);

$unique = array_unique($arr);

$duplicates = array_diff_assoc($arr, $unique);

print_r($duplicates);
Array ( [3] => 1 [6] => 4 [7] => 6 )

Example 2: check duplicate data in array php

$counts = array_count_values($array);
            $duplicate_title  = array_filter($array, function ($value) use ($counts) {
                return $counts[$value] > 1;
            });