Email deliverability is the rate at which your email messages reach the inbox of your intended recipients. It is one of the most important metrics to measure the success of your email marketing campaigns, as it directly affects your open rates, click-through rates, conversion rates, and revenue.

However, email deliverability services are not as simple as hitting the send button and hoping for the best. Many factors can affect whether your emails land in the inbox or get filtered out by spam filters, such as your sender’s reputation, authentication, content, user engagement, and more.

In this guide, we will cover everything you need to know about email deliverability, from the basics to the best practices, tools, and tips to improve your email performance and reach more people with your messages.

What is email deliverability and why does it matter?

Email deliverability is the ability of your emails to reach the inbox of your target audience without being blocked, bounced, or marked as spam by the email service providers (ESPs) or the recipients themselves.

Email deliverability matters because it directly impacts the effectiveness of your email marketing efforts. If your emails are not delivered to the inbox, they will not be seen, opened, clicked, or converted by your subscribers. This means you will miss out on valuable opportunities to build relationships, generate leads, increase sales, and grow your business.

According to a report by Validity, only 79.6% of legitimate emails reached their final destination in 2020. This means that more than 20% of emails were either blocked, bounced, or sent to the spam folder. That’s a lot of wasted potential and lost revenue.

Therefore, it is crucial to optimize your email deliverability and make sure your emails are reaching the right people at the right time with the right message.

How is email deliverability measured?

Email deliverability is measured by several key indicators that reflect how well your emails are performing in terms of reaching the inbox and engaging your subscribers. Some of the most common metrics to track are:

• Delivery rate: The percentage of emails that are accepted by the ESPs and delivered to the recipients’ mailboxes. It does not necessarily mean that the emails reached the inbox, as they could still end up in the spam or other folders. To calculate your delivery rate, divide the number of emails delivered by the number of emails sent and multiply by 100.
• Bounce rate: The percentage of emails that are rejected by the ESPs and returned to the sender as undeliverable. There are two types of bounces: hard bounces and soft bounces. Hard bounces occur when the email address is invalid, non-existent, or blocked. Soft bounces occur when the email address is valid but there is a temporary issue that prevents delivery, such as a full mailbox, a server problem, or a message size limit. To calculate your bounce rate, divide the number of bounced emails by the number of emails sent and multiply by 100.
• Spam complaint rate: The percentage of emails that are marked as spam or junk by the recipients. This indicates that they are not interested in receiving your emails or that they did not consent to receive them in the first place. Spam complaints can damage your sender’s reputation and affect your future deliverability. To calculate your spam complaint rate, divide the number of spam complaints by the number of emails delivered and multiply by 100.
• Open rate: The percentage of emails that are opened by the recipients. This shows how well you are capturing their attention and interest with your subject lines and sender name. However, the open rate is not a very accurate metric, as it depends on whether the recipients have enabled images or tracking pixels in their email clients. To calculate your open rate, divide the number of unique opens by the number of emails delivered and multiply by 100.
• Click-through rate (CTR): The percentage of emails that generate at least one click on a link or a call-to-action (CTA) button within the email body. This indicates how well you are engaging your subscribers with your content and driving them to take action on your offer or goal. To calculate your CTR, divide the number of unique clicks by the number of emails delivered and multiply by 100.
• Conversion rate: The percentage of emails that result in a desired outcome or action from the recipients, such as making a purchase, signing up for a trial, downloading a resource, etc. This shows how well you are persuading your subscribers to take the next step in your customer journey or sales funnel. To calculate your conversion rate, divide the number of conversions by the number of emails delivered and multiply by 100.

These metrics can help you evaluate your email deliverability performance and identify areas for improvement. However, they are not enough to give you a complete picture of your email deliverability. You also need to monitor other factors that can affect your email delivery, such as your sender reputation, authentication, spam score, inbox placement, and more.