may be this question had been asked, I've searched but still not confident about my problem.. my problem is checking valid date from string $a='23-June-11'; //valid $b='Normal String';//invalid I want to convert $a and $b using strtotime() before I do that, of course i want to validate whether $a or $b is a valid date format From $a i can get 23, 11 using explode function, but how about 'June'? using function above, 'June' is not numeric