What regex can I use to validate a number between 0 and 255?

Question

I want to validate number in range of 0-255

I have this expression

\'/^([0-1]?[0-9]?[0-9])|([2][0-4][0-9])|(25[0-5])$/\'

But this a

Answer 1

I played with it further, and here is regex for strict 0-255 range, without leading zeroes permitted:

'/^([0]|[1-9]\d?|[1]\d{2}|2([0-4]\d|5[0-5]))$/'