There will come a time when you ask whether this email address exists? And Ychecker's email address checking tool is the solution. Ychecker checks an email address with the following strict procedure.

Check email format correct
Check the domain name
Extract MX records from email address
Authenticate using SMTP
Check that the email address is disposable or not
In addition to the above features, Ychecker also has a special feature that can check whether a Gmail address exists or that gmail address requires confirmation of a phone number or not.

website: https://ychecker.com/