
Email Address Length FAQ - nreece
http://www.eph.co.uk/resources/email-address-length-faq/
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die_sekte
Wouldn't the shortest possible Email address be 3 characters long, as in
"a@b", where b is a TLD with a MX record, or did I failed to understand
something critical?

~~~
ars
You are correct. Although I don't think there are any TLD's with one letter.

Sean Hastings <sean@ai> seems to be real, and ai has an MX record.

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wizard_2
.ai seems to be a "personal TLD". Most of the websites I've found on the tld
(www.ai and nic.ai) are written in first person. The registrar (same person?)
takes 3 months to approve accounts after charges before giving you the domain,
dns changes are made on weekends, and 2nd level domains (ie hn.ai) are
reserved for residents and local companies. I don't have a problem with any of
that. I'm just curious how you find yourself in charge of such a setup.

~~~
die_sekte
It's the TLD of Anguilla, and Anguilla is quite small (population of 13000,
area just over 100 square kilometers), so most likely the internet of Anguilla
is maintained by just a few persons whose first priority isn't the TLD and the
domains in it.

Personal TLDs don't exist (at least as far as I know). Some registrars are
just tiny, AdamsNames for example which maintains .TC, .VG and .GD.

------
niyazpk
[edit: Looks like my view is just plain wrong. Skip this and directly read the
replies]

IMHO email address fields need not be 254 characters in length. Something like
64 is perfectly defendable I think.

Why would a person sign-up with an email address of 200+ characters if he is
not looking for a buffer overflow? Why would a sane person even bother to have
such a long email address? How much time would he take to type that?

He would have tried the email id on many other websites and some of them
should have rejected it. So the person obviously does have a shorter version
of his email address for those sites.

How would a person fill in the emial address in a paper form where there is
something like 30 fields for the email address?

I'd say 64 is enough. Anything above is just weird. I can do away with those
two users who have such long ids.

~~~
ankhmoop
Given that conforming with the standard is effectively free, do you have any
other justification for your non-conformal position of "I'd say 64 is enough.
Anything above is just weird"?

Willfully and capriciously ignoring standard requirements that you think are
"weird" results in non-conformal implementations that confound users and other
developers attempting to interoperate with your systems. I'm genuinely
surprised to be writing a paragraph defending standards conformance -- I'd
have thought that this position was _basic common sense_ among software
developers.

~~~
ubernostrum
Conforming with the standard is not "effectively free".

The only way to _really_ validate an email address is to try to send mail to
it. But that has non-zero cost (depending on how often you have to do it, what
the odds are that you'll end up on a spam blacklist for no good reason, etc.,
etc.).

The alternative is to use purely server-side validation routines. But these
become more and more expensive as you progress through less common edge cases
(e.g., regular expressions are not capable of detecting every valid address).
So most people, sooner or later, make a trade-off, favoring some more common
subset of cases over some less common subset.

If anything, we should be arguing over what constitutes an acceptable place to
make that trade-off. Should embedded comments be supported? What about bang
paths?

~~~
ars
If you are not going to email to it, why bother asking/storing it?

~~~
ubernostrum
Maybe you don't need to send email right away, but want to store the address
in case you need to get in touch with the user?

Sending one email per signup can be problematic depending on the volume of
signups. Sending email only when absolutely necessary can help with that.

~~~
ankhmoop
If you really care, use a real standards-comformant address parser, most
languages have at least one -- Java does. Otherwise you're just wasting your
time, and the time of any users you hose with your amateur-hour validation.

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akkartik
Isn't @a.gg (nothing before @) valid as an email address according to the RFC?
That was my conclusion last time I parsed it..

