To delete order in magento

Create  a delete-order.php file in root folder
and place this code

<?
require 'app/Mage.php';
Mage::app('admin')->setUseSessionInUrl(false);                                                                                                                
//replace your own orders numbers here:
$test_order_ids=array(
    '100000001',
    '100000075',
    '100000076',
    '100000077',
    '100000078',
    '100000079',
    '100000080',
    '100000081',
    '100000082',
    '100000083',
    '100000084'
);
foreach($test_order_ids as $id){
    try{
        Mage::getModel('sales/order')->loadByIncrementId($id)->delete();
        echo "order #".$id." is removed".PHP_EOL;
    }catch(Exception $e){
        echo "order #".$id." could not be remvoved: ".$e->getMessage().PHP_EOL;
    }
}
echo "complete."
?>