User Name
Pass Word:


Geek Question
Previous | Next by Dan 29 March, 2005 - 4:37 PM

What are the valid characters for an e-mail address

I have a list of the TLD's and ccTLD's

I know @ can't be the first chracter and . can not be the second character.

Yes you can have more than one @ in the e-mail. But are there any invalid characters or is the whole ASCII character set allowed?

3/30/2005 >> muhgcee

I actually have an email address that is

So I suppose . can be the second character.

I remember reading in a book one time that, according to standard, the range of allowable email addresses is quite wide (allowing for a lot of possibilities). But in practice, I remember reading, the range of possible addresses is cut down by restrictions that are not specified by whatever standard there is.

Hope this helped. It probably didn't.

3/30/2005 >> Dan

Ya thats a type-o a "." can not be the last character of the address string

But I found RFC 822 and if I'm right in my understanding of it. The only other rule is tha the domain name can not contain "\" and "/" but the account name can. The account name can even have mutiple "@'s" But, either way that is kinda silly since you can't have many of the ASCII charcters in the domain name. But it looks like the RFC 822 is from 1982.

But yes there are a lot of e-mail address validators that do confrom to the RFC. Most of the onse I saw in my research would also bust on the new TLD's (.info and such)

3/30/2005 >> ben

i'm assuming you're looking for a form validator of some kind with regular expressions?

3/30/2005 >> Dan

Nope just writing a test script....But using form valitadots as refrences since I could not find a straight answer

3/30/2005 >> ben

then yeah, i'm guessing the RFC is the way to go

You must be logged in to comment.


This is a Flickr badge showing public photos from Kheiligh. Make your own badge here.