To check how long one of your phpscript takes when executing, use the following code. It is a short and compact way to measure php script execution time.

$time_start = microtime(true); 
//your script here like:
$a = 2;
$b = 44;
$var = ($b * $a);

echo 'Total execution time in seconds is: ' . (microtime(true) - $time_start);