I'm sure you have your reasons for wanting to do this with a regular expression , but surely the smart way to do it would be: 

   $number >= 0 and $number <= 255

[download]
numeric comparison is going to be faster as that is something that computers can do natively.

/J\

In reply to Re: Regexp for range of numbers by gellyfish
in thread Regexp for range of numbers by loris

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