The Correct Way to Validate Email Addresses

Re:The Correct Way to Validate Email Addresses by Xorlev on Wednesday September 07, 2016 @10:56PM (#12449945)

At this point, our email validity criteria:

.+@.+\..{2,}

That is, at least one character for the inbox, at least one character for the domain, at least two for the TLD (we assume that TLD-less domains are undeliverable by us). This ensures we don't allow 'a@a' or '[email protected]', but do allow '[email protected]'.

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Re:The Correct Way to Validate Email Addresses by blechschmidt on Wednesday September 07, 2016 @11:14PM (#12450031)

This might already filter out legitimate users.

  dig MX io.

Also, you don't know what new TLDs ICANN might come up with at some point. I am pretty sure there are service providers that do and did limit the TLD length and then TLDs like xn--vermgensberatung-pwb came up.

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Re:The Correct Way to Validate Email Addresses by DHowett on Wednesday September 07, 2016 @11:14PM (#12450030)

a@[IPv6:2001::1] is, unfortunately for your validation regex, a valid e-mail address.

[EDIT: I see that you consider TLD-free e-mail addresses undeliverable; still!]

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Re:The Correct Way to Validate Email Addresses by bbcbasic on Thursday September 08, 2016 @01:05AM (#12450416)

  .+@.+

FTW?

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Re:The Correct Way to Validate Email Addresses by mnkypete on Thursday September 08, 2016 @03:29AM (#12450965)

That's what we do. Everything else is just lying to yourself and hoping for the best..

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Re:The Correct Way to Validate Email Addresses by Senji on Friday September 09, 2016 @02:18AM (#12459984)

Enjoy getting a billion e-mails per second written to root@localhost

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Re:The Correct Way to Validate Email Addresses by bbcbasic on Friday September 09, 2016 @03:37AM (#12460263)

As if. There would be a single confirmation email sent which would not be clicked.

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Re:The Correct Way to Validate Email Addresses by regularfry on Thursday September 08, 2016 @07:53AM (#12452138)

Or, more simply, `.@.`.

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Re:The Correct Way to Validate Email Addresses by zeveb on Thursday September 08, 2016 @11:12AM (#12453738)

That wouldn't allow ceo@cocacola, which is a valid email address (I don't know if mail will be delivered to it, but cocacola is an actual TLD).

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Re:The Correct Way to Validate Email Addresses by tobinfricke on Friday September 09, 2016 @12:42AM (#12459674)

Ian Goldberg once maintained the email address <n@ai>, touted as the shortest possible. An edge case, but it would fail your validation.

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