Validate Emails

Eric Meyer | March 25th, 2005 @ 11:13 am

Well, that’s that. I’ve finally seen something that looks more like line noise than Perl does.

Andy Skelton | March 25th, 2005 @ 11:16 am

Woah. Have you ever seen a regex that big? Somebody call a priest.

BenJ | March 25th, 2005 @ 11:40 am

*phew*! I’m glad someone else took the time — now I can spend it at the bar.

Noel | March 25th, 2005 @ 12:02 pm

The most insane thing I’ve ever seen.

Donncha | March 25th, 2005 @ 12:26 pm

Yes, but when the next person quoted the entire thing when replying with a one line comment on how incredible that regex was..
I’m glad commenting on blogs doesn’t automatically quote the post!

Denis de Bernardy | March 25th, 2005 @ 4:59 pm

Geez… Frankly…:

([\w]+\.)*([\w]+)@([\w]+)(\.[\w]+)+

is good enough. it’s not as of spammers were trying to insert emails as $^ù_`è.#’@&”~.com

Denis de Bernardy | March 25th, 2005 @ 5:00 pm

err, even:

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

but then, you go the point

Mr. Dew | March 26th, 2005 @ 12:32 am

That’s the longest regex I’ve seen!

Jonathan Fenocchi | March 26th, 2005 @ 5:34 am

Wow, that is long. I haven’t tested which works better, but this one has always worked fine for me:


/[^\x00-\x20()@,;:".[\]\x7f-\xff]+(?:\.[^\x00-\x20()@,;:".[\]\x7f-\xff]+)*\@[^\x00-\x20()@,;:".[\]\x7f-\xff]+(?:\.[^\x00-\x20()@,;:".[\]\x7f-\xff]+)+/i


Jonathan Fenocchi | March 26th, 2005 @ 5:34 am

Whoops, sorry about that horizontal scrollbar. (Can I edit my own comments somehow?)

Priyadi | March 27th, 2005 @ 4:12 am

I believe it is not how to match email address, but how to match the whole RFC822 address which includes one or more email address. An email address looks like this: john@example.com. But an RFC822 address may look something like “John Doe” <john@example.com>.

Observer | March 27th, 2005 @ 6:01 am

Wow: Is it before or after RSA encryption?

Jim | March 27th, 2005 @ 11:13 am

Heh. Now he has two problems.

There are lots of valid email addresses that typical regexps don’t catch. IIRC, the following is a valid email address: “a b c”@[127.0.0.1] - a regexp is really not enough to validate an email address, because you end up with a monstrosity like this (with all respect to the author).