{"id":27520,"date":"2023-09-12T22:02:22","date_gmt":"2023-09-12T19:02:22","guid":{"rendered":"https:\/\/snov.io\/knowledgebase\/?p=27520"},"modified":"2025-04-30T16:59:15","modified_gmt":"2025-04-30T13:59:15","slug":"how-email-verification-works","status":"publish","type":"post","link":"https:\/\/snov.io\/knowledgebase\/how-email-verification-works\/","title":{"rendered":"How Snov.io verifies emails"},"content":{"rendered":"<p>After reading this article, you'll understand how Snov.io verifies emails and what checks are performed on an email during verification process.<\/p>\n<p><strong><a href=\"#verification_checks\">Verification checks --&gt;<\/a><\/strong><\/p>\n<p><strong><a href=\"#valid_email\">What is a valid email --&gt;<\/a><\/strong><\/p>\n<p>Snov.io's <a href=\"https:\/\/snov.io\/email-verifier\" target=\"_blank\" rel=\"noopener\">email checker<\/a> helps you to accurately verify your list and clean it of outdated or incorrect emails before launching any campaigns.<\/p>\n<div class=\"notification-block note\">\n<div class=\"notification-block__icon\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/snov.io\/knowledgebase\/wp-content\/themes\/knowledgebase-n\/assets\/img\/ph_circle-wavy-warning.svg\" alt=\"note\" width=\"32\" height=\"32\" \/><\/div>\n<div class=\"notification-block__text\">\n<p><span style=\"color: #66b86a;\"><strong>Why use Snov.io's email verification:<\/strong><\/span><\/p>\n<p><span style=\"color: #66b86a;\">\u2022 Multiple verification checks to ensure precise results.<br \/>\n<\/span><\/p>\n<p><span style=\"color: #66b86a;\">\u2022 You'll be able to send only to valid emails and reduce deliverability risks. <\/span><\/p>\n<p><span style=\"color: #66b86a;\">\u2022\u00a0 Protect domain health and reputation. <\/span><\/p>\n<p><span style=\"color: #66b86a;\">\u2022\u00a0 Keep engagement rates high and reduce bounce rates.<\/span><\/p>\n<\/div>\n<\/div>\n<h2 id=\"verification_checks\"><strong>How Snov.io verifies emails<\/strong><\/h2>\n<p>To determine if the email address is valid, Snov.io runs it through a series of tests and combines different verification methods.<\/p>\n<p>This approach allows us to achieve the best possible accuracy.<\/p>\n<p>Here is a detailed checklist of verifications done for an email:<\/p>\n<p><strong>#1 Syntax check: <\/strong><\/p>\n<p>A syntax check during verification makes sure an email address is written correctly and follows the <a href=\"https:\/\/snov.io\/knowledgebase\/what-is-a-valid-email-address-format\/\" target=\"_blank\" rel=\"noopener\">basic rules of email format<\/a>. It checks for things like missing \"@\" symbols or extra spaces to ensure the email address is structured properly, like email@domain.com.<\/p>\n<p><strong>#2 Gibberish check:<\/strong><\/p>\n<p>A gibberish check helps spot emails that have been generated using random combinations of letters and symbols. These types of emails are often associated with fake, temporary, or disposable accounts.<\/p>\n<p><strong>#3 Domain name check:<\/strong><\/p>\n<p>This check ensures the accuracy of the domain name portion in an email address (e.g., \"company.com\"). It helps verify that the email address is associated with a working website.<\/p>\n<p><strong>#4 MX record check:<\/strong><\/p>\n<p>An MX record check involves checking a domain's settings to find its MX record. MX records indicate which mail servers handle emails for that domain.<\/p>\n<p>This process makes sure that the domain is ready to receive emails on the right email server. If an MX record is missing, the email doesn't pass the check.<\/p>\n<p><strong>#5 Email server check:<\/strong><\/p>\n<p>We send a connection request to the SMTP server specified in the domain's MX record. If the server responds promptly and positively, it indicates that the email server can accept incoming emails.<\/p>\n<p><strong>#6 Mailbox existence check:<\/strong><\/p>\n<p>We ping the SMTP server to inquire if an email address exists. Then, we wait for a response from the SMTP server to determine whether the email address exists.<\/p>\n<p><strong>#7 Catch-all check:<\/strong><\/p>\n<p>We check if the domain has a catch-all email server, which companies use to accepts all incoming emails into a special inbox, even if the intended recipient's mailbox no longer exists.<\/p>\n<p>If we confirm the presence of a catch-all server, the email address cannot be confirmed as valid.<\/p>\n<p>It means that if you send an email to any address within a particular domain, even if the address is nonexistent or contains errors, the catch-all mailbox will still receive your email.<\/p>\n<div class=\"notification-block tip\">\n<div class=\"notification-block__icon\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/snov.io\/knowledgebase\/wp-content\/themes\/knowledgebase-n\/assets\/img\/academicons_ideas-repec.svg\" alt=\"tip\" width=\"32\" height=\"32\" \/><\/div>\n<div class=\"notification-block__text\">\n<p class=\"whitespace-pre-wrap break-words\">When a company uses a \"catch-all\" email policy, this makes it impossible to confirm if the email address is valid.<\/p>\n<p class=\"whitespace-pre-wrap break-words\">In these cases, we mark the email as a yellow email (unknown status). While we can't guarantee these emails are valid, they might still work and be potentially valuable contacts.<\/p>\n<\/div>\n<\/div>\n<p><strong><a href=\"https:\/\/app.snov.io\/bulk-email-verification\" target=\"_blank\" rel=\"noopener\">Upload your list for email verification here --&gt;<\/a><\/strong><\/p>\n<p><strong>Bonus: Greylisting bypassing<\/strong><\/p>\n<p>Domains with email servers that use greylisting don't accept incoming connection requests they receive for the first time. It is a way to improve spam detection and reduce unwanted email traffic.<\/p>\n<p>When dealing with greylisting, we use a workaround method to achieve better accuracy.<\/p>\n<p>This ensures that potentially valid emails are not missed.<\/p>\n<p><strong><a href=\"https:\/\/snov.io\/knowledgebase\/what-is-greylisting-technology-and-why-does-verification-take-time\/\" target=\"_blank\" rel=\"noopener\">Learn more about greylisting and how Snov.io overcomes it --&gt;<\/a><\/strong><\/p>\n<h2 id=\"valid_email\"><strong>What is a valid email and why some emails cannot be verified<\/strong><\/h2>\n<p>As a result of verification, we classify email addresses and assign statuses that indicate their validity and deliverability risk.<\/p>\n<p>An email address is considered valid if it has successfully passed all verification checks and is safe for sending.<\/p>\n<p>Email addresses that couldn't be verified with 100% confidence during the verification checks receive the <strong>\"Unverifiable\"<\/strong> status.<\/p>\n<p><a href=\"https:\/\/snov.io\/knowledgebase\/email-statuses\/\" target=\"_blank\" rel=\"noopener\"><strong>Learn more about possible email statuses here --&gt;<\/strong><\/a><\/p>\n<h2><strong>What's next: follow email best practices<\/strong><\/h2>\n<p>Sending campaigns to verified emails is crucial. However, it's just one piece of the puzzle.<\/p>\n<p>The most accurate email verification alone won't solve everything. Various factors affect your email deliverability and bounce rate.<\/p>\n<p>These include low sender reputation and engagement rates, recipients marking your emails as spam.<\/p>\n<p>To ensure your sender domain stays healthy and boost your deliverability rates when using Snov.io to send emails, read the following helpful resources:<\/p>\n<ul>\n<li><strong><a href=\"https:\/\/snov.io\/knowledgebase\/how-to-increase-reply-rate-with-email-best-practices\/\" target=\"_blank\" rel=\"noopener\">Read about email deliverability best practices --&gt;<\/a><\/strong><\/li>\n<li><strong><a href=\"https:\/\/snov.io\/knowledgebase\/how-to-avoid-spam-filters\/\" target=\"_blank\" rel=\"noopener\">Learn how to avoid spam filters --&gt;<\/a><\/strong><\/li>\n<li><strong><a href=\"https:\/\/snov.io\/knowledgebase\/how-to-fix-bounce-rate-issue\/\" target=\"_blank\" rel=\"noopener\">Deliverability checklist: how to reduce bounce rate in campaigns --&gt;<\/a><\/strong><\/li>\n<\/ul>\n<p><em>If you still have questions, read the <a href=\"https:\/\/snov.io\/knowledgebase\/email-verifier\/\" target=\"_blank\" rel=\"noopener\">FAQ section<\/a> and find the answers you're looking for.<\/em><\/p>\n<p><em><span style=\"font-weight: 400;\">If this article does not address your question, feel free to contact our Customer Care team at <a href=\"mailto:help@snov.io\">help@snov.io<\/a>.<\/span><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>After reading this article, you&#8217;ll understand how Snov.io verifies emails and what checks are performed on an email during verification process. Verification checks &#8211;&gt; What is a valid email &#8211;&gt; Snov.io&#8217;s email checker helps you to accurately verify your list and clean it of outdated or incorrect emails before launching any campaigns. Why use Snov.io&#8217;s [&hellip;]<\/p>\n","protected":false},"author":16,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"_links":{"self":[{"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/posts\/27520"}],"collection":[{"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/users\/16"}],"replies":[{"embeddable":true,"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/comments?post=27520"}],"version-history":[{"count":5,"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/posts\/27520\/revisions"}],"predecessor-version":[{"id":39322,"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/posts\/27520\/revisions\/39322"}],"wp:attachment":[{"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/media?parent=27520"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/categories?post=27520"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/snov.io\/knowledgebase\/wp-json\/wp\/v2\/tags?post=27520"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}