{"id":36563,"date":"2025-11-12T09:36:33","date_gmt":"2025-11-12T09:36:33","guid":{"rendered":"https:\/\/www.bancomail.com\/blog\/?p=36563"},"modified":"2026-03-19T10:23:54","modified_gmt":"2026-03-19T10:23:54","slug":"b2b-email-validation-smtp-server","status":"publish","type":"post","link":"https:\/\/www.bancomail.com\/blog\/en\/b2b-email-validation-smtp-server\/","title":{"rendered":"B2B Email Validation: what happens when you query an SMTP server"},"content":{"rendered":"\n
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Whassup?! The Sound of Our Email Validator<\/p>\n<\/blockquote>\n\n\n\n

Over the past few months, one of the trickiest technical challenges we\u2019ve tackled has been building our very own Email Validator<\/strong><\/a> – to make our database more reliable than ever.<\/p>\n\n\n\n

Of course, we\u2019ve been checking email addresses for a long time (selling B2B databases without validating emails is reckless and can land buyers in serious blacklisting trouble – always make sure addresses are valid!). Until recently, we relied on solid existing tools. There are plenty of them, some excellent, and we even built great collaborations with a few. But we noticed some inconsistencies and inaccuracies that pushed us to invest both brainpower and budget<\/strong> into developing a modern, safe, and fully functional tool that gives us solid, reliable answers.<\/p>\n\n\n\n

Creating a tool like this means getting your hands dirty<\/strong>.
No skimming the surface here: you have to dive into the complex workings of mail servers and protocols – without getting lost along the way.<\/p>\n\n\n\n

At the heart of validation is the dialogue with the recipient\u2019s server. To explain it simply, we like to use an analogy everyone familiar with classic American pop culture will get: the legendary \u201cWhassup?!\u201d phone call.<\/strong><\/p>\n\n\n\n

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