Script execution time in PHP is the time required to execute the PHP script. To calculate script execution time use clock time rather than the CPU execution time. Knowing clock time before script execution and after script execution will help to know the script execution time.
Example: Sample script
Clock time can get using microtime() function. First use it before starts the script and then at the end of the script. Then using formula (End_time – Start_time). The mirotime() function returns time in seconds. Execution time is not fixed, it depends upon the processor.
Execution time of script = 1.6927719116211E-5 sec