[PHP] 생년월일로 (만)나이 계산

// 만나이 계산
 public static function age_kor($birthday) {
    $today       = date('Ymd');
    $birthday = date('Ymd' , strtotime($birthday));
    $age     = floor(($today - $birthday) / 10000);
    return $age;
 }

// 나이 계산
public static function age($birthday) {
   $today    = date('Y');
   $birthday  = date('Y' , strtotime($birthday));
   $age      = $today - $birthday + 1;
   return $age;
}