Get min and max value in PHP Array

foreach ($array as $k => $v) {
  $tArray[$k] = $v['Weight'];
}
$min_value = min($tArray);
$max_value = max($tArray);

Option 1. First you map the array to get those numbers (and not the full details):

$numbers = array_column($array, 'weight')

Then you get the min and max:

$min = min($numbers);
$max = max($numbers);

Option 2. (Only if you don't have PHP 5.5 or better) The same as option 1, but to pluck the values, use array_map:

$numbers = array_map(function($details) {
  return $details['Weight'];
}, $array);

Option 3.

Option 4. If you only need a min OR max, array_reduce() might be faster:

$min = array_reduce($array, function($min, $details) {
  return min($min, $details['weight']);
}, PHP_INT_MAX);

This does more min()s, but they're very fast. The PHP_INT_MAX is to start with a high, and get lower and lower. You could do the same for $max, but you'd start at 0, or -PHP_INT_MAX.

For the people using PHP 5.5+ this can be done a lot easier with array_column. Not need for those ugly array_maps anymore.

How to get a max value:

$highest_weight = max(array_column($details, 'Weight'));

How to get the min value

$lowest_weight = min(array_column($details, 'Weight'));