--- title: "Periodic Table of Deliverability Score | DuoCircle" description: "Ever wanted to understand some of the elements that impact your deliverability, take a look at the Periodic Table of Email deliverability." image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/blog/outbound-smtp/periodic-table-deliverability-score/" --- Quick Answer The Periodic Table of Email Deliverability is a visual reference that maps the elements affecting whether your messages reach the inbox: configuration issues, sending options, authentication, content, and reputation factors. It is a quick way to scan the common reasons messages get held up before arrival. Share [ ](https://www.linkedin.com/sharing/share-offsite/?url=undefined%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F "Share on LinkedIn") [ ](https://twitter.com/intent/tweet?text=Periodic%20Table%20of%20Deliverability%20Score&url=undefined%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F "Share on X/Twitter") [ ](https://www.facebook.com/sharer/sharer.php?u=undefined%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F "Share on Facebook") [ ](https://reddit.com/submit?url=undefined%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F&title=Periodic%20Table%20of%20Deliverability%20Score "Share on Reddit") [ ](mailto:?subject=Periodic%20Table%20of%20Deliverability%20Score&body=Check out this article: undefined%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F "Share via Email") ![Email deliverability](https://media.mailhop.org/duocircle/images/2018/03/spf-record-check-6230.jpg) Ever wanted to understand some of the elements that impact your deliverability, take a look at the [Periodic Table of Email deliverability.](https://blog.moosend.com/email-deliverability/) It outlines the common issues, configurations and sending options that could be keeping your messages from making it to the inbox. ![Brad Slavin](https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg) Brad Slavin General Manager General Manager at DuoCircle. Product strategy and commercial lead across the email security portfolio. ## Secure your email infrastructure Protect, authenticate, and deliver. Contact our team to find the right solution. [Contact Sales](/contact/) [Explore Products](/products/) Share this article [ ](https://www.linkedin.com/sharing/share-offsite/?url=https%3A%2F%2Fwww.duocircle.com%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F) [ ](https://twitter.com/intent/tweet?text=Periodic%20Table%20of%20Deliverability%20Score&url=https%3A%2F%2Fwww.duocircle.com%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F) [ ](https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fwww.duocircle.com%2Fblog%2Foutbound-smtp%2Fperiodic-table-deliverability-score%2F) Copy Related Articles - [ Office Copiers Can't Authenticate to Microsoft 365 Anymore: Why It Broke and How to Fix It SMTP ](/blog/office-copiers-cant-authenticate-to-microsoft-365-the-fix/) - [ ![SMTP Plugins](https://media.mailhop.org/duocircle/images/2020/11/SPF-record-checker-5236.jpg) A Quick Guide To 5 Free SMTP Plugins For Your Domain SMTP ](/blog/outbound-smtp/a-quick-guide-to-5-free-smtp-plugins-for-your-domain/) - [ ![Email Marketing](https://media.mailhop.org/duocircle/images/2020/05/spf-flattening-5245.jpg) All You Need To Know When You Buy SMTP Server For Email Marketing SMTP ](/blog/outbound-smtp/all-you-need-to-know-when-you-buy-smtp-server-for-email-marketing/) - [ ![Blacklisted Email](https://media.mailhop.org/duocircle/images/2018/01/SMTP-email-7563.jpg) The Blacklisted Email IP: The Digital Pariah That Can Impact Your Business SMTP ](/blog/outbound-smtp/blacklisted-email-ip-digital-pariah-can-impact-business/) ## Related Articles [ SMTP 7m Office Copiers Can't Authenticate to Microsoft 365 Anymore: Why It Broke and How to Fix It May 5, 2026 ](/blog/office-copiers-cant-authenticate-to-microsoft-365-the-fix/)[ SMTP 3m A Quick Guide To 5 Free SMTP Plugins For Your Domain Nov 20, 2020 ](/blog/outbound-smtp/a-quick-guide-to-5-free-smtp-plugins-for-your-domain/)[ SMTP 5m All You Need To Know When You Buy SMTP Server For Email Marketing May 19, 2020 ](/blog/outbound-smtp/all-you-need-to-know-when-you-buy-smtp-server-for-email-marketing/)[ SMTP 8m The Blacklisted Email IP: The Digital Pariah That Can Impact Your Business Jan 6, 2018 ](/blog/outbound-smtp/blacklisted-email-ip-digital-pariah-can-impact-business/) ```json {"@context":"https://schema.org","@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. 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