Mail tester, your choice for a complete tool

After spending a lot of time trying to automate my processes, particularly on checking the emails I have on my software, and after talking with people in the field, I looked for a complete solution that could check with great precision in my email lists. I then looked at https://mailtester.ninja/ which in addition to being very complete, offers an API.

So my question is whether any of you have other tools, other methods? thank you

Good morning, I just tested your tool and I find it efficient in addition to being cheap... I used Hunter before but Ninja Mail allowed me to test more email addresses in a given time.

Mail tester, your choice for a complete tool
 
 
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