Email addresses are not always the original and valid ones, which are given by users, mostly scammers. So you need to check every email address that you work with, is valid or not.

Like, if someone comments in your blog post where you sell something, they comment leaving some wrong email address, and after the comment is left, they would get what they want but you left with an invalid email address. So better be cautious before sending an email.

Here are a few online tools that verify the email address and let you know whether you are sending the email to the right address, well formatted and a valid one.

1. Email unlimited verification tool -
This tool checks the email address by connecting to the domain name of the email host, then to the email address to verify it. It verifies the following -
Format: “address@domain.xxx”
Valid domain: “smith@new.york” is not valid
Valid user: Verify that the user and mailbox really exist

2. Verify Email -
The same work as the first tool.

3. Hexillion Email Validation -
Found this tool a bit slower one but it works and functions a bit process than the other two, as it connects to the IP addresses and email clients etc. and is one of the accurate ones to use. Uses Email Dossier utility to validate the email address.

This is how the first 2 tools work -