Hi rsriram,

Here is one way to do it.

$str = 'a[bdy]dfjaPÑsdafÜ';

while ($str =~ /[^!-~\s]/g)
{
    print "Non ASCII Characater:\t$&\n";
}

Another way:

while ($str =~ /[^[:print:]]/g) 
{
    print "Non Printable Characater:\t$&\n";

}
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If you would have super searched, you would have got detecting non-ascii chars in a string, Getting rid of non-standard ASCII characters and more similar nodes.