Date::Calc has a check_date function. From the docs:

if (check_date($year,$month,$day))
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This function returns ``true'' (``1'') if the given three numerical values ``$year'', ``$month'' and ``$day'' constitute a valid date, and ``false'' (``0'') otherwise.

For example:

use strict;
use warnings;

use Date::Calc qw( check_date );

my ( $year, $month, $day ) = ( 2006, 1, 30 );

printf "[$year, $month, $day] %s a valid date\n",
    check_date( $year, $month, $day ) ? 'is' : 'is not';

( $year, $month, $day ) = ( 2006, 1, 32 );

printf "[$year, $month, $day] %s a valid date\n",
    check_date( $year, $month, $day ) ? 'is' : 'is not';

( $year, $month, $day ) = ( 2006, 2, 29 );

printf "[$year, $month, $day] %s a valid date\n",
    check_date( $year, $month, $day ) ? 'is' : 'is not';
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This prints:

[2006, 1, 30] is a valid date
[2006, 1, 32] is not a valid date
[2006, 2, 29] is not a valid date
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