You need to add an outermost set of parentheses. /^((19[5-9]\d)|(20(([0-4]\d)|50)))$/

I don't know why, but I'm always paranoid when using | in a regex, primarily because I don't know exactly how it works. (I need to read Mastering Regular Expressions, I know ...)

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In reply to Re: Re: Matching date range with pure regex by dragonchild
in thread Matching date range with pure regex by BUU

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