How to clear the database from non-working emails?

Question

gmail

A simple subscription form is installed on my site, through which 15 thousand subscribers signed up for the newsletter (without checking the email). All emails are stored in my database.

According to Exim logs, I see that many emails are not working and I deleted them, about 500-1000 emails. But I'm sure there are still a lot of junk emails in the database.

Maybe there is some good service for checking emails, I would even look in the direction of paid ones.

I guess that all this can be done through subscription services like mailchimp, unisender, smartresponder, etc. maybe someone did that?

Answer 1

You can do this:
1. Check the validity of the input using a regular expression or in other ways (http://habrahabr.ru/post/108475/)
2. Then you can implement verification using MX records (http://habrahabr.ru/sandbox/ 60991/). This will also help to reject some of the non-working emails.

Answer 2

What is the need for removal? The volume is more than modest. Why are they expensive to keep?
Mail addresses cannot be checked against mail server reports and their response headers. To check, get yourself a box on rambler and chat with the mail server.
Regulars can cut off a lot of valid addresses, because According to the specification, before @ can be anything, the restriction is only in length. Google - there are well-known answers on this topic on SO.

Answer 3

There are services, but they are quite expensive. I use www.briteverify.com/

Answer 4

All checks in Mailchimp etc. are also tied to receiving and parsing responses from the mailer daemon. The best, in my opinion, way to destroy "extra" subscribers is to tag all links and pictures in emails with unique values, collect statistics on clicks and downloads of pictures, and remove comrades from the mailing list who have never opened or clicked anything, for example , within 1-3 months.

Answer 5

You will first run all records using regular expressions, then check for the existence of an MX record for the domain and then try to connect to each domain and ask SMTP for the existence of the email. It would not hurt to run spam traps and “honeypots” through the databases.
If you are too lazy to do this, write, we will agree;)

Answer 6

I wrote a Python script that checks MX for now, this is enough, weeded out about 15% of emails, before deleting them from the database, I first visually assessed them, almost all of them looked like generated or simply expired domains. My mailing list is not commercial, if you suddenly deleted several working emails - it's not scary.

Answer 7

Here he wrote a detailed instruction on the topic of checking all kinds of bases for validity: read .