Here is an enhancement: you can use a hash to show all guesses and to notify the user that a guess was already used. I also fixed your range check to match your printed advice (1 to 100). Finally, I used perltidy.

use Modern::Perl;

my $target = ( int rand 100 ) + 1;
my $number = 99;

my %guesses;
GUESS: foreach my $guess_num ( 1 .. $number ) {
    say "($guess_num) Please enter a guess:";
    my $guess = <>;
    chomp $guess;

    if ( ($guess =~ /\D/) or ($guess > 100) or ($guess == 0) ) {
        say "This guess is out of range. Guess between 1 and 100!";
        redo GUESS;
    }

    if ( $guess == $target ) {
        say "Congrats, you guessed right!";
        last GUESS;
    }

    elsif ( exists $guesses{$guess} ) {
        say "You already guessed $guess.";
    }

    elsif ( $guess < $target ) {
        say "Your guess of $guess was too small.";
    }

    elsif ( $guess > $target ) {
        say "Your guess of $guess was too big.";
    }

    $guesses{$guess}++;

    print "your previous guesses: ", join ' ', sort {$a <=> $b} keys %
+guesses;
    print "\n";

    if ( $guess_num == $number ) {
        say "You have used all your guesses. Please try again.";
        last GUESS;
    }
}
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