I am looking for an Email checker tool that would be fast and can handle bulk verification at a time and would be high in performance 

I have heard good things about <a href=https://email-checker.net/”>Email Checker</a>and
<a href=”https://emailidator.com/”>Emailidator</a>  but I am not sure which one is better for high performace. I am also open to other suggestions.

Thanks in Advance.