<?php
  function dirSize($directoty){
    $dir_size=0;
    if($dir_handle=@opendir($directoty))
    {
      while($filename=readdir($dir_handle)){
        $subFile=$directoty.DIRECTORY_SEPARATOR.$filename;
        if($filename=='.'||$filename=='..'){
          continue;
        }elseif (is_dir($subFile))
        {
          $dir_size+=dirSize($subFile);
        }elseif (is_file($subFile)){
          $dir_size+=filesize($subFile);
        }
      }
      closedir($dir_handle);
    }
    return ($dir_size);
  }
  $dir_size=dirSize("xym");
  echo round($dir_size/pow(1024,1),2)."KB";
?>