How to improve this Regex?

Question

I wrote this regex to identify US type phone numbers:

\(?\d{3}\)?(-|\s)\d{3}-\d{4}

This works for phone numbers like:

217-244-2424 and (217) 244-2424.

However it also works for unbalanced parenthesis like (217-244-2424

How can the regex be improved to make sure the parenthesis are balanced? (I'm aware of the questions on regex phone numbers asked before, but I couldn't find what I was looking for from there.)

possible duplicate of [A comprehensive regex for phone number validation](http://stackoverflow.com/questions/123559/a-comprehensive-regex-for-phone-number-validation) — johnsyweb, Mar 07 '13 at 07:33

score 2 · Answer 1 · answered Mar 07 '13 at 07:38

2

I will answer you specific question on regex. You can try something like this to handle paranthesis:

^(\(\d{3}\)|\d{3})-(\d{3})-(\d{4})$

answered Mar 07 '13 at 07:38

manojlds

290,304
63
469
417

score 0 · Accepted Answer · answered Mar 07 '13 at 07:39

0

I have not tested it, but why not using the alternation operator ("|")? You could choose to have either both parenthesis, or none of them:

(\(\d{3}\)|\d{3})(-|\s)\d{3}-\d{4}

answered Mar 07 '13 at 07:39

JonasVautherin

7,297
6
49
95

Thank u. That was simpler than I thought. – user2063763 Mar 07 '13 at 07:49

How to improve this Regex?

2 Answers2