<?php 

// Starting clock time in seconds 

$start_time = microtime(true); 

$a=1; 

// Start loop 

for($i = 1; $i <=1000; $i++) 

{ 

    $a++; 

}  

// End clock time in seconds 

$end_time = microtime(true); 

// Calculate script execution time 

$execution_time = ($end_time - $start_time); 

echo " Execution time of script = ".$execution_time." sec"; 

?>