Email marketing is an essential part of digital communication. Over 347 billion emails are sent and received every day, a number that continues to grow. With this volume, brands must pay close attention to email deliverability to ensure their messages reach intended inboxes instead of being lost or flagged as spam.
During the pandemic, email usage skyrocketed, and today there are more than 4 billion daily email users worldwide. Unfortunately, not every email gets delivered successfully. Some messages bounce back, while others end up in spam folders.
The good news is that you can improve email deliverability with the right tools and processes. By using proper email delivery testing platforms and working with marketing automation specialists, you can diagnose problems, take corrective action, and maximize campaign performance.
Two popular tools to get started are Mail-Tester.com and MXToolbox. These platforms help identify common issues that affect deliverability and provide actionable recommendations for improvement.
Test the spamminess of your emails by using a mail tester.
Mail-Tester.com is a user-friendly and intuitive free online service, that tests the quality of your email. By sending a test email to Mail-Tester.com, you can receive a report indicating the likelihood that your email will be labeled as spam by different email filters. The report provides a score out of 10 and includes recommendations on how to improve your email's deliverability.
Needless to say: you should aspire for a score as high as possible. If your configuration is done right and you don't have issues in the Spam area, your score shouldn't be below 8.5.
One crucial aspect of email deliverability is ensuring your email passes authentication checks. This is where SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) come in. These two protocols are used to verify the authenticity of emails and prevent email spoofing and phishing.
The tool provides recommendations on how to improve your email deliverability based on the issues detected. These recommendations may include suggestions to improve the content of your email, optimize your subject line, or fix any technical matters with your email server. As you can see in the picture below, in the case of this platform, every tab has a drop-down that shows your particular issues and how to solve them.
Still, don't rely exclusively on these aspects concerning spam triggering. An excellent email is not enough if you do not control the number of emails sent through practices like touch governance, contact fatigue management or custom preference center. You can learn more about how not to trigger that spam emotional response from here.
Aside from all this, Mail-Tester can also show you whether or not you are blacklisted. But we'll talk about this more below.
MXToolbox is another popular online platform for free, fast, and accurate network diagnostic and lookup tools. It provides a comprehensive suite of diagnostic instruments that can help IT professionals and system administrators troubleshoot issues related to email delivery, DNS records (meaning database records used to map a URL to an IP address), and network connectivity.
When you test your email deliverability, it’s recommended to check your DNS records for a domain or IP address. This can be useful for troubleshooting issues related to DNS configuration, such as email delivery, website accessibility, or domain name resolution.
One particular feature of this platform we want to focus on in this article is the email delivery testing service. Although this comes before email deliverability, it’s recommended to check both. Hence, it's only natural to check that your email is delivered (meaning it won't bounce back) and then verify whether it ends up in your audience's Inbox, Spam folder, or another folder. You can test various aspects, including DNS records, MX configuration, and spam filter settings. By identifying and resolving these issues, you can ensure that emails get to the recipients' inboxes without delays or issues.
(Good DMARC example)
(SPF Record Issues example)
(Good SPF Record example)
Email blacklist
Here's the thing, email deliverability is a pretty vast subject, and the list of possible issues can be long and very subjective. So is the list of handy tools and services.
Some other aspects you should consider at this step of your implementation are blacklist monitoring, port scanning, and SSL certificate testing.
An IP address blacklist check shows if your URL or IP address has been listed by any key email provider or anti-spam organization (aka a domain name server blacklist or DNSBL). Many DNSBLs exist online, each using different criteria for listing and delisting addresses. Thus, it is essential to beat the clock to it and ensure that email providers do not mark your emails as spam or blacklist you entirely.
When testing your emails, you must learn to take advantage of detailed reports and analyses of network performance and email delivery. This data can help you identify trends and patterns and identify potential issues before they become major problems. Hence, using proper tools to evaluate your emails and taking improvement actions should be your go-to in every project.
Final thoughts
Email deliverability is a vital part of marketing automation success. Tools like Mail-Tester and MXToolbox provide clear insights into performance, configuration, and potential risks.
By combining proper testing, DNS management, and email authentication (SPF, DKIM, DMARC), you can ensure that your messages consistently reach recipient inboxes.
If deliverability challenges feel overwhelming, consider working with email marketing automation specialists who can streamline the process and guide your strategy.
The time and effort invested in improving deliverability pay off through stronger engagement, better results, and a healthier email marketing program.
