# mounth-day-year
function getAge($date){
$bday = explode("-", $date, 3);
$bday = mktime(0,0,0,$bday[0],$bday[1],$bday[2]);
$age = (int)((time()-$bday)/31556926 );
return $age;
}

#eg:
echo getage("03-27-1990"); # returns the age.

Calculate Age using PHP (mounth-day-year to age)

php

PHP