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Check If Email Exists

github.com

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121–130 of 260 posts

Re: Check If Email Exists

#121

Post by 3np »

Interesting tool, but there are some really concerning dark antipatterns here that I really despise:

  Is the address provided by a known disposable email address provider?
  Is the email address bound to a known free email provider?
  Does email address under test hide a honeypot?
What are the legit use-cases for this? To be sure you can force spam on your users and identify them as ad-targets?

Re: Check If Email Exists

#122

Post by bobthebuilders »

SilverRed wrote: post #64
dmd wrote: post #29

It thinks the email address I've used for more than 25 years is invalid. Great job.

There is really no point validating emails beyond checking there is an @ in the address. Send an email to verify. You can even have an address with no . if you own the tld. foobar@me is a valid email.

Incorrect, I tried sending a mail and it bounced.

Re: Check If Email Exists

#123

Post by JoshTriplett »

benlivengood wrote: post #116
Semaphor wrote: post #103

Earlier quoted context omitted.

That’s you (and the large part of HN who doesn’t know anything about normal users). When GDPR came into effect, we even had people write us that they were annoyed having to reconfirm, as obviously they still wanted our newsletter.

Some people want to receive marketing emails. The exact same emails are spam to the rest of us. If you default opt-in users and don't make blanket unsubscription from all marketing emails easy (and make the clear distinction [both internally and externally] between emails regarding the existing functionality of products/services that we've already paid for and emails to ask for more revenue from us, which includes co…

> If you default opt-in users and ... then you're a spammer, simple as that.

There is no "and". If you default opt-in users, you're a spammer.

> Spammers aren't necessarily evil

What?

Re: Check If Email Exists

#124

Post by nextaccountic »

neeleshs wrote: post #112
wyager wrote: post #91

Earlier quoted context omitted.

I've never once received a "marketing email" that wasn't spam.

Used to be in the same camp, before starting my own company. While the border is thin, it is clear, and there is a difference between marketing and spam.

I think you proved the point: when the spammer send spam they think they are doing marketing.

Re: Check If Email Exists

#125

Post by jhugo »

The accepts_mail test seems flawed; a domain with no MX records can still accept mail (the spec requires an MTA to connect to the IP address in the A/AAAA record of the domain part of the mail address in this case).

All MTAs that I’m aware of support this, and it’s moderately common on personal domains with a single self-hosted MX, rare as those are these days.

Re: Check If Email Exists

#126

Post by cyberCleve »

maddyboo wrote: post #68
Cyberdog wrote: post #8

Could someone spell out a use case for this? One that comes to mind would be validating that a mailing list doesn't have any outdated email addresses in it, but couldn't that be determined by just checking for a bounce when a message is sent to it? I tried to sign up for SiriusXM the other day, and though I could create an account with my .pro email address, I couldn't actually sign up for service with that same addr…

I just watched a video where someone demo’d GitHub Copilot by writing a comment along the lines of // IsValidEmail takes a string and returns whether it’s a valid email address The AI response was a nightmarish 100+ character regex that made my blood curdle. I think of email validation like encryption: don’t roll your own, and don’t trust an AI to do it either. Edit: Here's the regex: https://gist.github.com/cassidoo…

Does it work?

Re: Check If Email Exists

#127

Post by SilverRed »

bobthebuilders wrote: post #122
SilverRed wrote: post #64

Earlier quoted context omitted.

There is really no point validating emails beyond checking there is an @ in the address. Send an email to verify. You can even have an address with no . if you own the tld. foobar@me is a valid email.

Incorrect, I tried sending a mail and it bounced.

It is a valid email if the owner of the me tld sets up an email address on it. I'm not sure if anyone has done it on a tld but I have seen websites which are on the tld with no sub domain.

Re: Check If Email Exists

#128

Post by vxNsr »

user3939382 wrote: post #25
gh2k wrote: post #21

I hope nobody uses this for anything serious. I run my own domain and use - @ to have a unique email for everything I sign up to. I have no email address that this counts as anything other than "risky". If this opts me out of marketing mail then that's probably a good thing, but I hope nobody puts a password-reset or security/billing notifications behind it.

I’ve been doing the same thing for years and haven’t had any trouble except for Mailchimp. Their overly-clever validation decided mailchimp@example.com is a shared email account (it wasn’t going to be) and blocked me from using it. Their email support apologized but said they couldn’t fix the false positive, and that they hoped the email I used instead wasn’t reflective of my opinion: mailchimp-morons@example.com.

Do you have a personal set up for managing these emails and disabling the bad ones? or are you using something like 33mail? Just curious.

Re: Check If Email Exists

#129

Post by iudqnolq »

smileysteve wrote: post #4

The SMTP way of checking if an email exists is on the wrong side of CANSPAM, beginning the sending process to check an address is specifically addressed. And this assumes you didn't systematically "guess" the address.

CAN-SPAM regulates "sending electronic mail messages". Connecting to an SMTP server to ask it if an address exists doesn't sound like that to me, but IANAL.

Re: Check If Email Exists

#130

Post by nemosaltat »

Cyberdog wrote: post #8

Could someone spell out a use case for this? One that comes to mind would be validating that a mailing list doesn't have any outdated email addresses in it, but couldn't that be determined by just checking for a bounce when a message is sent to it? I tried to sign up for SiriusXM the other day, and though I could create an account with my .pro email address, I couldn't actually sign up for service with that same addr…

Similar experiences here. I have [myfirstname]@[mylastname].party as my primary email. In meatspace it’s a curiosity, and people are sometimes incredulous. Online, I’m routinely given some variant of “enter a valid email address.”
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