RegEx for validating emails

Question

I searched this site and found many threads that deal with this topic. But don't know why none of them realized that email formats vary a lot and not limited to xxx@ddd.com or something like this as for example xxxx@ddddd.rr.com is valid email address and so is xxx@ddd.museum . I tried almost all regular expressions that can be found for validating emails, none worked for this validation. Then there are emails with .info, .museum, etc.

I am very poor at regular expressions. Just wondering if someone can write a very broad express that checks for "at least one @ and one or more dots, no comma). I understand it will not work perfectly but at least it will not reject valid email addresses.

The regex from [this](http://stackoverflow.com/a/8829363/247893) thread [works fine](http://regex101.com/r/aR5tG1)? — h2ooooooo, Feb 06 '14 at 16:24
don't, see http://stackoverflow.com/questions/201323/using-a-regular-expression-to-validate-an-email-address?rq=1 — Fredrik Pihl, Feb 06 '14 at 16:24
Just use a char search to check for @.there was a top level domain with an mx record at one point — user1937198, Feb 06 '14 at 16:30
As input to your regex, are you sending a string of text including a possible email address, or just the potential email address itself. — Jon Senchyna, Feb 06 '14 at 18:55

Donnie Rock · Answer 1 · 2014-02-07T08:42:42.437

1

I though this could works: \b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]+\b

edited Feb 07 '14 at 08:42

answered Feb 06 '14 at 16:27

Donnie Rock

552
1
14
27

mmmm, try this: `\b[A-Z0-9._%+-]+@(?:[A-Z0-9-]+\.)+[A-Z]\b` – Donnie Rock Feb 06 '14 at 17:19
@DonnieRock You are close, but you are only matching a single character after the last dot. – Jon Senchyna Feb 06 '14 at 18:58
Ups, I forget the `+` after the last `]`. Thanks @JonSenchyna! – Donnie Rock Feb 07 '14 at 08:49
Also, unless you're specifying case-insensitivity in the code running your regex, it only handles uppercase. You'd need to replace `A-Z0-9` in your character sets with `a-zA-Z0-9` or `\w` (which also captures '_'). – Jon Senchyna Feb 07 '14 at 12:30

score 0 · Accepted Answer · answered Feb 06 '14 at 16:33

0

My best bet is \w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*. This rocks.

Its official Microsoft's email regex, which i got from my visual studio ultimate 2013 :)

answered Feb 06 '14 at 16:33

Amit Joki

58,320
7
77
95

Please look at this: http://en.wikipedia.org/wiki/Email_address#Valid_email_addresses dot is not mandatory in the domain part, `myemail@com` is a valid address. – Toto Feb 07 '14 at 09:31

score 0 · Answer 3 · answered Feb 06 '14 at 19:06

Since your question seems to be focused on capturing what comes after the '@', I'll simply post the regex for that. The following should work for you:

@((\w+(-+\w+)*\.)+\w+(-+\w+)*\b

To break it down, this will capture:

@
At least one repetition of a "word" (that can include, but doesn't begin or end with a dash) followed by a dot: ((\w+(-+\w+)*)\.)+
A final "word" (again, that can include, but doesn't begin or end with a dash): \w+(-+\w+)*\b

To break down the "word" regex \w+(-+\w+)*), I'm capturing:

At least one alpha-numeric character \w+
Any number of the following:
1. At least one dash -+ followed by
2. At least one alpha-numeric character \w+

RegEx for validating emails

3 Answers3