Something like this, maybe? 
use strict;

while (my $data = <DATA>) {
  chomp $data;
  
  if ($data =~ /^\d?\d?\d\.\d\d?\d?$/) {
    print "GOOD\n";
  } else {
    print "BAD\n";
  }
  
}

__DATA__
12.12
123.123
0.1
1234.0
1234

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In reply to Re: Need a regex.. by scorpio17
in thread Need a regex.. by littlemonk

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