Validate email really exists

As above, there is no truly 'good' way to do this which isn't likely to cause more problems than it solves. You would need to get knee deep in the nitty-gritty of SMTP, and make a call on 'philosophical' questions such as 'does a mailbox which returns a soft bounce message count as existing?'.

Which is why the standard 'we will send you an email, click a link in it to validate' approach is normally used.

One of the reasons it is so difficult to check if an email exists (without sending an email) is that spammers could then brute force every valid email for a domain.

Yes! correct, many email provider companies block this validation such as gmail and others don't thus making any validation method unrealiable. I gave up on this one.

For example here http://verify-email.org/ it really checks that gmail accounts exist. I guess it can be done after all.

Hey Andy,

If you`re looking for a tool that does all kind of verifications of an email adress, I recommend https://thechecker.co

I`ve been using it for single email verification and it is very reliable.

Hey Andy,

I used to use hunter.io, but its just too expensive.

I found a service that is, by far, the most inexpensive one out there. Its called https://sparkemail.net

Its very accurate as well.

Hope this helps :-)

This is how some one else did it.

php-smtp-email-validation

Read the article.

What did you Try? What did you Get? What did you Expect?

Joined CodeIgniter Community 2009.  ( Skype: insitfx )

All email checkers and verifiers perform the basic function of checking format, domain, and the presence of a mailbox on a server using SMTP tests, helping you clean your email lists and reducing your risk of being marked as spam. For these purposes I use https://proofy.io It's the most accurate single email or bulk list verification service.