Ultimate Guide to Email Marketing Metrics

Written by Shane Herring
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Last updated: September 3, 2023

Apprentice, Growing

This isn’t an exhaustive list. However, it is a list of metrics relevant to many micro-business owners at some point.

A warning. It would be impractical for a micro-business owner to try and monitor all of these metrics.

Services are available to bring all these metrics into a single dashboard, but the costs tend to be beyond the budget of most micro-business owners.

Now the metrics.

Each metric has been put into a group according to its role. For example, subscriber engagement metrics are used to measure the behaviour of subscribers. Revenue metrics relate to the financial impact of using email marketing.

Table of Contents

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Subscriber engagement metrics

The email marketing metrics in this section give some insight into what subscribers are doing with your emails.

It’s important to note that subscriber engagement metrics tend to be the most inaccurate. This is because they rely on being able to track what subscribers are doing. Many email clients provide the ability to disable any form of tracking. And that’s a good thing. Metrics such as open rate don’t give meaningful information anyway.

To counter the inaccuracy, consider them a good comparative metric. Track the trend over time. This indicates what subscribers as a group are doing. If the open rate for the entire group is low, you can be confident that the open rate for recipients who aren’t tracked will also be low.

With that out of the way, on to the first metric.

Open rate

What is open rate?

This email marketing metric calculates the percentage of recipients who opened an email.

But it’s an inaccurate metric. The reasons for this include:

Why it matters

As mentioned, it’s an inaccurate metric but it does help to understand the behaviour of recipients as a group.

Recording and monitoring the trend helps understand how the group is engaging with emails. If the trend is increasing, it’s an indicator that the group as a whole is opening your emails. Even if you don’t know whether some individuals are, or aren’t opening emails.

If the trend is decreasing, the group as a whole isn’t opening emails.

The metric is inaccurate from your point of view. The email service that received it will notice when a recipient opens the email. This is engagement and improves email deliverability to that service. Always monitor the trend and take steps to move that trend upwards.

How to calculate it

Here’s the formula for calculating the open rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 100 bounced. That’s 1,400 emails that were assumed to be delivered.

1,000 of those emails were opened.

Open rate = (1,000 / (1,500 – 100)) x 100 = 71.43%

In this example, the open rate is 71.43%.

How to improve open rates

Open rates can be improved by using tactics that include:

Create engaging subject lines. Write compelling subject lines that are concise, relevant, and create a sense of urgency or curiosity.

Personalisation. If you’re not using personalisation, start using it. Especially in the subject line, preheader, or greeting. If you are using it, vary how emails are personalised. Try other tactics.

Segmentation. Segment your email list to send emails that are relevant to the reader.

Optimise send times. Test different send times to determine when your target audience is most likely to open and engage with emails.

Mobile optimisation. Ensure that your emails are designed using the mobile-first principle. Designing emails to be read on smaller screens and creating mobile-friendly content can improve mobile open rates.

Remove disengaged subscribers. Regularly clean your email list to remove inactive or disengaged subscribers. A smaller, more engaged list will likely result in higher open rates.

Avoid spam triggers: Not all spam emails are sent to the spam folder. Some emails can be rejected as soon as an email service deems your emails to be untrustworthy.

Use Safelisting. Encourage recipients to reply to your email or add your email address to their address book, safelist, or contact list. This helps improve deliverability and reduces the chances of your emails being sent to the spam folder.

Open reach

What is open reach?

Open reach is the percentage of recipients who opened at least one of your emails in a defined period.

Why it matters

Not all recipients will open all of your emails all of the time. Some will view the email in preview mode which generally isn’t identified as an open. Some readers don’t display images.

Open reach is a good email marketing metric to account for infrequent openers. If your open rate is low, open reach can give more insight because it takes into account those infrequent openers. Instead, it helps understand how your subscribers as a group are responding to your emails.

By tracking the percentage of people who are engaged with your emails rather than the percentage of emails that were opened, you’re going straight to what you’ve always wanted to know in the first place: how many people engage with your emails.

How to calculate it

Here’s the formula for calculating the open reach rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say that in the last three months, 1,200 subscribers opened at least one email. In that same period, you had 1,500 subscribers.

Open reach = (1,200 / 1,500) x 100 = 80%

In this example, the open reach is 80%.

How to improve open reach

Use the same tactics to improve open reach as you would use to improve open rates.

Mobile open rate

What is mobile open rate?

The mobile open rate is the percentage of recipients who opened an email from devices such as phones and tablets. This helps you understand the reading behaviour of your recipients.

It’s also inaccurate for the same reasons that the open rate is inaccurate.

And usually, mobile open rates will be lower than desktop devices.

Why it matters

This is another metric that helps to understand the reading behaviour of recipients.

If your mobile open rate is relatively high compared to open rates for desktops, it may indicate that your readers are opening emails while they’re travelling to work or relaxing at home in the evening.

How to calculate it

Here’s the formula for calculating the mobile open rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 500 were opened on mobile devices.

Of those 1,500 emails, 50 bounced. That’s 1,450 emails that are assumed to have been delivered.

Mobile open rate = (500 / (1,500 – 50)) x 100 = 34.48%

In this example, the mobile open rate is 34.48%.

How to improve mobile open rates

Design emails in line with the mobile-first principle. If an email is displayed correctly on a mobile device, it will display correctly on a desktop device.

Use the same tactics to improve mobile open rates as you would use to improve ‘normal’ open rates.

Domain open rate

What is domain open rate?

The domain open rate is the percentage of emails opened by recipients who use a specific email service. For instance, you could calculate the domain open rate for emails sent to gmail.com.

While this can be easily measured for most consumer recipients, it’s more difficult to learn which service is being used for a business email address.

Why it matters

The results can help you understand how recipients using different email services engage with your emails.

It can also indicate how trustworthy your emails are to the receiving email service. For instance, if the domain open rate for Yahoo Mail recipients is significantly lower than recipients using Gmail, Yahoo Mail may be blocking your emails.

How to calculate it

Here’s the formula for calculating the domain open rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you want to measure the domain open rate for emails sent to Gmail users.

Imagine you sent 1,500 emails and 20 bounced. That’s 1,480 emails that were delivered.

Of those 1,500 emails that were sent, 750 were sent to Gmail email addresses and 350 of those recipients opened the emails.

Domain open rate = (350 / (1,500 – 20)) x 100 = 23.65%

In this example, the domain open rate is 23.65%.

How to improve the domain open rate

Use the same tactics to improve domain open rates as you would use to improve ‘normal’ open rates.

Non-open rate

What is non-open rate?

The non-open rate is the opposite of the open rate. It’s the percentage of recipients who are not opening emails.

Non-open rate is inaccurate for the same reasons that the open rate is inaccurate.

And like open rates, track the non-open rate trend.

Why it matters

If the focus is on the open rate, it’s easy to ignore the trend showing the number of people who aren’t opening emails. And this is the number we should be more concerned about.

It’s possible that the open rate is increasing but so is the non-open rate. It’s just a matter of numbers. If the non-open rate is trending upwards, this can have an impact on deliverability.

Even though it’s inaccurate, it’s inaccurate from the email marketing service point of view. The email service that received it will notice when recipients aren’t opening your email. Because they’re not engaging with your emails, that can harm the deliverability of emails going to that service.

How to calculate it

Here’s the formula for calculating the non-open rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

Calculate the number of emails not opened by subtracting the number of emails opened from the number of emails sent.
Calculate the number of emails delivered by subtracting the number of email bounces from the number of emails sent.
Divide the number of emails not opened by the number of emails delivered.
Multiply the result by 100 to convert it into a percentage.

For example, let’s say you sent 1,500 emails and 1,300 were opened. The number of non-opens is 200.

Of those 1,500 emails that were sent, 100 bounced. That’s 1,400 emails that were delivered.

Non-open rate = (1,500 – 1,300) / (1,500 – 100) x 100 = 14.28%

In this example, the non-open rate is 14.28%.

How to improve the non-open rate

Use the same tactics to improve mobile open rates as you would use to improve ‘normal’ open rates.

Click-through rate (CTR)

What is click-through rate?

Click-through rate, also known as click rate, is the percentage of recipients who selected at least one link or call to action in an email.

It helps to understand how engaged recipients are.

This metric can be inaccurate because email services may follow the call to action to validate the destination. They do this as part of their spam-checking algorithms.

Why it matters

It’s the first real indicator of email engagement. An email open is just an open. It tells you that the recipient may have been interested in what you have to say. Clicking a call to action indicates that your message body has encouraged the reader to take the next step. Think of the click-through rate as an indicator of how effective your calls to action are.

To better understand the behaviour of all recipients, track trends.

Like open rate, a recipient clicking a call to action is engagement and email services notice engagement.

How to calculate it

Here’s the formula for calculating the click-through rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 1,300 recipients selected a call to action. 100 of those emails bounced.

Click-through rate = (1,300 / (1,500 – 100)) x 100 = 92.86%

In this example, the click-through rate is 92.86%.

How to improve click-through rate

Click-to-open rate (CTOR)

What is click-to-open rate?

It’s the percentage of recipients who opened an email and clicked at least one link or call to action.

Why it matters

Inaccuracy aside, this metric is an indicator of how engaged your readers are.

This email marketing metric helps you understand:

How to calculate it

Here’s the formula for calculating the click-to-open rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 1,400 recipients opened that email. Of those 1,400, 900 clicked the call to action.

Click-to-open rate = (900 / 1,400) x 100 = 64.28%

In this example, the click-to-open rate is 64.28%.

How to improve CTOR

There are several ways for you to improve CTOR:

Create subject lines and preheader text that set the right expectations.
Write copy that shows the reader the benefit of clicking the call to action.
Remove unnecessary elements from the email so the reader isn’t distracted.
Create calls to action that stand out on the page and lead the reader to click on them.

Mobile click rate

What is mobile click rate?

The mobile click rate is the percentage of recipients who clicked a call to action while using a mobile device.

And if you guessed that mobile click rates would be an inaccurate metric, you’d be correct. Well done.

Also, mobile open rates will usually be lower than desktop devices.

Why it matters

This is another metric that helps to understand the reading behaviour of recipients.

If your mobile click rate is relatively high compared to click-through or click-to-open rates for desktops, it indicates that more readers are engaging with emails while they’re travelling to work or relaxing at home in the evening.

Monitoring mobile click rates for users of different devices can give some insight into the experience mobile users have when engaging with your emails.

How to calculate it

Here’s the formula for calculating the mobile click rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and there were 500 clicks of a CTA. Of the 1,500 emails sent, 25 bounced. That’s 1,475 emails that were assumed to be delivered.

Mobile click rate = (500 / (1,500 – 25)) x 100 = 33.9%

In this example, the mobile click rate is 33.9%.

How to improve mobile click rate

Some ways to improve the mobile click rate include:

Domain click rate

What is domain click rate?

The domain click rate is the percentage of calls to action clicked by recipients who use a specific email service. For instance, you could calculate the domain click rate for recipients with a Gmail address.

It’s a useful metric to learn if specific email services are changing the format of emails.

Determining the email service used by business recipients can be difficult.

Why it matters

The results can help you understand how recipients using different email services engage with your emails.

If recipients using a specific email service aren’t clicking calls to action, it may indicate a problem. For instance, if domain click rates for Yahoo Mail recipients are significantly lower than recipients using Gmail, Yahoo Mail may be altering the calls to action.

How to calculate it

Here’s the formula for calculating the domain click rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 100 bounced. That’s 1,400 emails that were assumed to be delivered.

500 emails were sent to recipients who use Gmail and of those, 250 selected a call to action.

Mobile click rate = (250 / (1,500 – 100)) x 100 = 17.85%

In this example, the mobile click rate is 17.85%.

How to improve the domain click rate

If there is a significant difference between email services, send an email to a test email account created on the domain with reduced clicks. Check that the layout is correct and the link takes the reader to the correct destination.

To improve domain click rates overall, use the same tactics that you would use to improve ‘normal’ click-through rates.

Email conversion rate

What is email conversion rate?

It’s the percentage of readers who completed a specific call to action.

That call to action may have been to read a specific blog post, visit an online store, or sign up for a webinar.

Why it matters

It helps measure the effectiveness of your marketing campaign. It answers the question, “What percentage of readers took the specific action I wanted them to take?”

Without knowing how effective an email campaign was, it’s difficult to know if the campaign achieved the desired outcome.

How to calculate it

Here’s the formula for calculating the email conversion rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

Then, follow these steps.

For example, let’s say you sent 2,500 emails and 100 bounced. That’s 2,400 emails that were assumed to be delivered.

From those that were delivered, 2,000 recipients clicked the primary call to action.

Email conversion rate = (2,000 / (2,500 – 100)) x 100 = 83.33%

In this example, the email conversion rate is 83.33%.

How to improve email conversion rate

To improve email conversion rate:

Use segmentation: Sending content relevant to that reader increases engagement.
Compelling subject lines: Create attention-grabbing subject lines that encourage the recipient to open the email.
Clear, focused content: Keep your email copy focused on getting the reader to click the primary call to action.
Strong calls to action: Make your call to action stand out on the page. Make good use of contrasting colours and white space. Use action-oriented language that tells the reader what action to take.
Mobile-first design: Emails must be displayed correctly on different devices. Design emails for small screens and they’ll be readable on all devices.
Use social proof: Use social proof to build trust and credibility with your readers.
Make good use of scarcity and urgency: People don’t like missing out. Use limited-time offers, countdown timers, or exclusive deals.

Email forward rate

What is email forward rate?

It’s the percentage of recipients who forwarded the email. It’s usually only measurable if the email includes a special link provided by the email marketing service.

This is another positive engagement metric. It shows that your recipient thought your email may be useful to someone in their circle of influence.

Why it matters

Encouraging recipients to forward emails is a list growth tactic. This is particularly useful if the email solves a specific problem. Asking the recipient to forward the email to someone they know has the same problem can result in new subscribers.

It’s also useful to develop brand advocates. People who consider the information you’ve given them so valuable that they need to share it with their network.

Another outcome of a recipient sharing an email is to increase revenue. Encourage the reader to forward the code to people who may want to save money.

How to calculate it

Here’s the formula for calculating the email forward rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 25 bounced. That’s 1,475 emails that were assumed to be delivered.

Of those, 40 emails were forwarded.

Email forward rate = (40 / (1,500 – 25)) x 100 = 0.03%

In this example, the email forward rate is 0.03%.

How to improve email forward rate

Increasing the email forward rate can expand your audience. It gets your emails into the inboxes of people who aren’t subscribers. And does it correctly.

Personalisation: Create content that ‘speaks’ directly to the reader. If it’s highly personalised, it will be more likely that they will share it with others who have similar interests.
High-Quality Visuals: Incorporate eye-catching images, infographics, or videos to make your emails visually appealing and share-worthy.
Useful Information: Provide valuable insights, tips, or exclusive offers that recipients would find helpful and want to pass along.

"Forward to a friend" button: Add a prominent button that allows readers to easily forward the email to their contacts with a single click.
Incentives for Forwarding: Offer incentives, such as discounts or exclusive content, for recipients who forward the email to others.
Social Media Integration: Include social media sharing buttons to enable recipients to share the email content with their followers.

Reward System: Offer rewards, such as discounts, freebies, or loyalty points, to both the referrer and the new subscriber they bring in through the referral.
Exclusive Benefits: Provide exclusive benefits or access to premium content for subscribers who participate in the referral program.
Limited-Time Offers: Create a sense of urgency by setting a deadline for the referral program or offering limited-time rewards.

Email sharing rate

What is email sharing rate?

This is the percentage of readers who share your email. The links to share are usually provided by an email marketing service.

Why it matters

Encouraging recipients to share your content is another list growth tactic. Like the email forward, a recipient is more likely to share an email if it solves a specific problem. Asking the recipient to share the email on their social media channels can result in new subscribers.

It’s also useful to develop brand advocates. People who consider the information you’ve given them so valuable that they need to share it with their network.

Another outcome of a recipient sharing an email is to increase revenue. Encouraging the reader to share a discount code can help drive traffic to a store.

How to calculate it

Here’s the formula for calculating the email sharing rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 10 bounced. That’s 1,490 emails that were assumed to be delivered.

Of those, 55 emails were forwarded.

Email sharing rate = (55 / (1,500 – 10)) x 100 = 3.7%

In this example, the email sharing rate is 3.7%.

How to improve email sharing rate

Use the same tactics to improve email sharing rates as you would use to improve email forwarding rates.

Bounce rate

What is bounce rate?

This is the percentage of emails that could not be successfully delivered to the recipient.

There are two types of email bounces:

Soft bounce: This happens when a message could not be delivered at that time because of a temporary problem. Problems such as the recipient’s inbox is full.

Hard bounce: This happens when a message could not be delivered because of a permanent problem. Problems such as the email address no longer exists.

Why it matters

Many reasons will cause an email to bounce. Research the bounce codes to learn why your email bounced.

More importantly, if you continue to send emails that bounce, email services will consider you untrustworthy and reject all your emails.

How to calculate it

Here’s the formula for calculating the bounce rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 25 bounced.

Bounce rate = (25 / 1,500) x 100 = 1.67%

In this example, the bounce rate is 1.67%.

How to improve bounce rate

There isn’t a lot you can do to reduce the number of soft bounces. Emails can soft bounce for reasons outside of your control.

For hard bounces, steps to take include:

Using an email validation process such as double opt-in or an email validation service
Ensuring authentication is configured correctly. This is important if you’re not using your email marketing service to authenticate your emails.
Consistently send content your readers love. This improves engagement and reduces the chances of your emails being rejected.
Remove disengaged recipients. Disengagement could be due to an email address becoming invalid.
Run spam checks on your emails. To make sure that your content isn’t being seen as spam.
Allow readers to update their email addresses. If your content is seen as valuable, many readers will change their email addresses when they need to.

Spam complaint rate

What is spam complaint rate?

The spam complaint rate is the percentage of emails reported as spam. There are three ways an email can be flagged as spam.

A recipient unsubscribes and gives the reason for unsubscribing as they felt the email was spam.

A recipient uses an email service to report an email as spam. That service may pass the report back to the email marketing service. Spam complaints will be a combination of complaints from email services and the email marketing service.

An email service may reject an email that was identified as spam. That service will return a spam-related bounce code.

Why it matters

Spam complaints are negative engagement. The recipient engaged with your email but not in the way that you want.

Email services notice when their users mark an email as spam. If enough users mark your emails as spam, all your emails to all their users will be treated as spam whether the recipient marked them or not.

If your email marketing service notices a high spam complaint rate, they may suspend your account while they investigate.

How to calculate it

Here’s the formula for calculating the spam complaint rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 100 bounces. That’s 1,400 emails that were assumed to be delivered.

Of those 1,400 emails that were delivered, you received 10 spam complaints.

Spam complaint rate = (10 / (1,500 – 100)) x 100 = .71%

In this example, the spam complaint rate is .71%.

How to improve spam complaint rate

Improving the spam complaint rate is a simple process. But it needs to start at the beginning of your email marketing journey.

Only send to contacts who have explicitly opted in. Don’t send to email addresses obtained in other ways.
Don’t send emails to subscribers if you haven’t sent them emails for a year or more. Some may forget who you are and that they signed up.
Make sure the email used to sign up is valid. Use an email validation service or a double opt-in process.
Make the unsubscribe process easy. If it’s not easy, it’s likely your email will be marked as spam instead. An unsubscribe is better than a spam complaint.
In the first series of emails, remind the reader why they’re receiving an email from you.
Make sure your emails are what they signed up for.
Make sure your emails come from the same domain where contacts signed up and make sure the email has the same branding. Be sure the "From" name for your campaign aligns closely with the branding of the page where contacts signed up.

Unsubscribe rate

What is unsubscribe rate?

The unsubscribe rate is the percentage of recipients who chose to opt out of your mailing list after receiving an email.

If a subscriber was unsubscribed by the list administrator, don’t include these in the calculation. This is because the reader didn’t choose to stop receiving your emails.

Why it matters

In general, people unsubscribing is a good thing. It means that the readers on your list are the ones interested in hearing from you.

However, a sudden increase in the unsubscribe rate should be investigated.

It could suddenly increase because you’ve been list-bombed. If this is the case, you should also see a sudden increase in spam complaints.

It can also suddenly increase when you’ve merged lists from different organisations. If this is going to happen, it’s important to let readers know beforehand that the sender will change.

If you’ve invested heavily in growing your list, it could also indicate that you either attracted the wrong audience or you’re not sending the content you promised.

How to calculate it

Here’s the formula for calculating the unsubscribe rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 100 bounces. That’s 1,400 emails that were assumed to be delivered.

1,000 of those emails were opened.

Open rate = (1,000 / (1,500 – 100)) x 100 = 71.43%

In this example, the open rate is 71.43%.

How to improve unsubscribe rate

Understand that people will unsubscribe. It’s a natural part of email marketing. It’s not always about you (see spam complaint rate) but it could be.

Use these tactics to improve your unsubscribe rate.

Deliver what the reader signed up for. While people may sign up for a lead magnet, make it clear that they may also receive marketing emails.
Send emails at the right frequency for the reader. Sometimes emails might be sent too often. Sometimes they may not be sent often enough. If you’re not sure, give the reader the choice. The other option is to let readers choose how often they receive your emails. It’s ok to send emails more frequently if you have a special offer for the reader.
Make sure the subject line relates to the message content. If they open an email and it’s not what they expected, they may unsubscribe.
Use segmentation to send content relevant to the reader.

Cart recovery rate

What is cart recovery rate?

It’s the percentage of online shopping carts that were recovered.

The shopper completed their order after an abandoned cart sequence was sent.

Why it matters

It’s estimated that, on average, 70% of online shoppers don’t complete a purchase. On average, 50% of shoppers who receive an abandoned cart sequence engage with those emails. And if only one of those people completes their purchase, that’s a sale.

For anyone using an abandoned cart sequence, this is a critical metric to monitor. It’s an indicator of how effective the abandoned cart sequence is at recovering potentially lost sales.

How to calculate it

Here’s the formula for calculating the cart recovery rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say your online store had 1,200 shopping carts abandoned.

Of those abandoned carts, 300 shoppers went on to complete their orders.

Cart recovery rate = (300 / 1,200) x 100 = 25%

In this example, the cart recovery rate is 25%.

How to improve cart recovery rate

A low recovery rate shows that an abandoned cart sequence may be needed or an existing abandoned cart sequence isn’t effective.

Send the first abandoned cart sequence email between one and two hours after the item was put into the cart.

If you sell a lower price-point item, consider sending this email sooner, say 15-30 minutes after cart abandonment.

The email design should include:

a creative subject line
a conversational tone
product information including an image
a call to action that links directly back to their cart
contact information that can be used if there was a problem.

List management metrics

The metrics in this section help manage an email list. They help you manage specific areas of email marketing such as how fast a list is growing, how many emails are arriving in the inbox, and how long a subscriber remains on a list.

List management metrics are unreliable but not for the same reason that engagement metrics are. One reason they’re unreliable is that the information needed to calculate the results isn’t available on the email marketing service. Another reason is that email services don’t share information.

But, tracking trends over time and monitoring those trends for sudden increases or decreases will decrease the impact of any problems.

List growth rate

What is list growth rate?

It’s the percentage growth, or reduction, of an email list.

It helps you understand how many subscribers you’re gaining or losing.

Why it matters

On average, subscriber numbers will reduce by 25% each year. It’s part of email marketing.

If you consider that subscribers joining your email list are leads, if you want more sales, you need to grow your email list.

By calculating your email list growth rate, you can measure the effectiveness of your lead generation efforts. However, if you’re not actively running lead capture campaigns, this metric won’t have much to offer.

How to calculate it

Here’s the formula for calculating the list growth rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say for the month of June, you gained 100 new subscribers and had five people unsubscribe. That’s a net gain of 95 subscribers.

At the end of June, you had a total of 2,000 subscribers.

List growth rate = ((100 – 5) / 2,000)) x 100 = 4.75%

In this example, the list growth rate was 4.75%.

How to improve list growth rate

The list growth rate can be improved by increasing the number of subscribers and reducing the number of unsubscribes.

To increase the number of subscribers:

To reduce the number of unsubscribes:

Inbox placement rate

What is inbox placement rate?

It’s the percentage of emails that were delivered to a recipient’s inbox as opposed to being rejected or sent to the recipient’s spam folder.

For Gmail and Google Workspace recipients, tabs such as Promotions and Social are part of the inbox.

Why it matters

A low inbox placement rate indicates that email services consider your emails as untrustworthy. It’s a symptom of a wider problem.

If your emails aren’t delivered to the inbox, recipients can’t open them, read them, or act on your calls to action. This will affect conversion rates.

How to calculate it

IPR is usually measured by sending a test email to a group of subscribers and tracking how many of those recipients received the email in their inboxes. There are inbox placement testing services available. Each uses a different method to test inbox placement.

For small-scale testing, use a seed list of 10 – 15 test email accounts that you control.

Here’s the formula for calculating the inbox placement rate.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 10 emails to a seed list and none bounced.

9 of those emails arrived in the inbox.

Inbox placement rate = (9 / (10 – 0)) x 100 = 90%

In this example, the inbox placement rate is 90%.

How to improve inbox placement rate

While it might seem difficult to recover from a low inbox placement rate, using a few tactics will get your emails back to the inbox.

Depending on our sending frequency, send only to your most engaged readers for a few weeks. This will help build trust with email services.

Make sure your email authentication is set up correctly. Authentication is an important trust factor.

Use a reputable email marketing service. Email services want the sending service to be just as trustworthy.

Delivery rate

What is delivery rate?

The delivery rate refers to the percentage of sent emails that successfully reach the recipients’ inboxes without bouncing back. It’s an indicator of the effectiveness of a deliverability strategy.

Why it matters

While it might seem that tracking bounce rates achieves the same result, tracking delivery rates puts the focus on email delivery rather than non-delivery.

Getting an email delivered is the first challenge when sending marketing emails. If marketing emails aren’t being delivered, nothing else matters.

How to calculate it

Here’s the formula for calculating the delivery rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you sent 1,500 emails and 30 bounced.

Deliver Rate = ((1,500 – 30) / 1,500) x 100 = 98%

In this example, the delivery rate is 98%.

How to improve delivery rate

Keeping your email list clean and up to date is the best way to maintain a strong deliverability rate in the long term. Don’t hesitate to remove disengaged subscribers from your list!

Here are some other tips.

Use an email validation process such as double opt-in or an email validation service
Ensure authentication is configured correctly. This is important if you’re not using your email marketing service to authenticate your emails.
Consistently send content your readers love. This improves engagement and reduces the chances of your emails being rejected.
Remove disengaged recipients. Disengagement could be due to an email address becoming invalid.
Run spam checks on your emails. To make sure that your content isn’t being seen as spam.

Churn rate

What is churn rate?

It’s the percentage of subscribers who are no longer active in a specified timeframe.

This could be subscribers who chose to unsubscribe, were manually removed, or their email address hard-bounced.

Churn can also include subscribers who haven’t unsubscribed but aren’t reading your emails. They are disengaged.

Why it matters

Churn isn’t concerned with new subscribers. The focus is squarely on the percentage of subscribers leaving or being removed from a list.

Knowing your curn rate helps you understand whether or not your content is resonating with your audience. The effort you put into reducing the churn rate will increase open, click-through, click-to-open, and unsubscribe rates.

How to calculate it

Here’s the formula for calculating the churn rate.

Here’s a step-by-step explanation of the formula.

For this formula, several pieces of information are needed.

The timeframe to be analysed. Annually is easier.
The number of active subscribers at the start of the period.
The number of subscribers who unsubscribed during that period.
The number of emails that hard bounced during that period.
The number of spam complaints during that period.
The number of inactive subscribers during that period. This includes subscribers who were removed manually as a result of being disengaged. Include subscribers who have not engaged at least once in the 12 months before the start of the timeframe being analysed.

Then, follow these steps.

For example, at the start of the year, there were 5,000 active subscribers.

During the year, there were 200 unsubscribes, 50 bounced emails, 10 spam complaints, and 240 inactive subscribers manually removed. A total of 500.

Churn rate = (500 / 5,000) x 100 = 10%

In this example, the churn rate is 10%.

How to improve churn rate

To improve the churn rate, you need to:

Use surveys to learn the types of content your readers want.
Use segmentation to deliver relevant content.
Let recipients choose the content they’re interested in and how often they receive it.
Use a re-engagement sequence to encourage engagement from disengaged subscribers.
Get feedback when readers unsubscribe to reduce future unsubscribe rates.

Average subscriber lifespan (ASL)

What is average subscriber lifespan?

This is the average length of time a subscriber remained on your list before they unsubscribed.

The key is to record when they subscribed and when they unsubscribed or were removed from the list.

Current, active subscribers aren’t included because they’re still active.

Why it matters

This is a good indicator of list health. A longer average subscriber lifespan indicates that email content, frequency, and overall engagement strategies are resonating with readers. If subscribers value your emails, they’re more likely to continue engaging with your emails for a longer period.

However, a shorter average could indicate potential problems with your overall email marketing approach. Your content may not be meeting the expectations of subscribers. You may be sending too often or not often enough. You may not be attracting the right audience for your business.

How to calculate it

Here’s the formula for calculating the average subscriber lifespan.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say the sum of the durations was 1,200 years or 14,400 months. 400 subscribers are no longer active.

Average subscriber lifespan (years) = 1,200 / 400 = 3

Average subscriber lifespan (months) = 14,400 / 400 = 36

In this example, the average subscriber life span was 3 years or 36 months.

How to improve average subscriber lifespan

To increase the average subscriber lifespan, there are several tactics to focus on.

Deliver content that is relevant, personalised, and gives value to your readers. Understand what they’re interested in and how you can solve their problems.
Use segmentation to increase the relevance of your emails to each reader.
Find the right balance for the frequency of your emails. Sending too many without the option to reduce the frequency could increase unsubscribes.

Email opt-in conversion rate

What is email opt-in conversion rate?

It’s the percentage of website visitors who successfully joined a mailing list through a sign-up form.

Why it matters

It helps you understand how effective a website is at attracting new leads.

A high opt-in conversion rate shows that visitors are reacting positively to the value proposition. A lower rate suggests that improvements need to be made.

The results can also change depending on where the sign-up form is displayed. This can include the page displaying the form and the form’s position on the page.

For instance, landing pages tend to have better conversion rates than other page types such as the home page or blog posts.

Take this metric further, and analyse results for a landing page. Comparing landing page results to other pages can give some insight into the effectiveness of lead-generation tactics that drive traffic to that landing page.

How to calculate it

Here’s the formula for calculating the email opt-in conversion rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then, follow these steps.

For example, let’s say you had 5,000 website visitors. 500 of those subscribed to your list.

Email opt-in conversion rate = (500 / (5,000 – 100)) x 100 = 10%

In this example, the email opt-in conversion rate is 10%.

How to improve opt-in conversion rate

This metric measures the effectiveness of page and form copy. To improve opt-in conversion rates:

Make sure your opt-in forms have clear and persuasive call to actions that communicate the benefits of subscribing.
Tell visitors what value they will receive if they’re on your email list.
Position your forms strategically on your website or landing pages so that they stand out and are easy to use.
Keep the opt-in process simple. On ask for the minimum information.
Offer a high perceived value incentive in return for their email address. Make those offers relevant to the content they’re viewing.
Ensure your opt-in forms are mobile-friendly and easy to use on small screens.
Include trust signals, such as privacy policy links.
Use exit-intent popups to capture visitors who are about to leave the site without subscribing.

Re-engagement rate

What is re-engagement rate?

This is the percentage of previously inactive subscribers who respond to your re-engagement efforts.
They indicated they want to continue receiving your emails even though they haven’t engaged with them.

Why it matters

It’s important to measure how effective your re-engagement campaigns are. It tells you how many inactive subscribers are being retained.

A high re-engagement rate is a positive sign, as it shows that your re-engagement efforts are effective in bringing back disengaged subscribers. On the other hand, a low re-engagement rate might indicate the need to review and optimize your re-engagement strategies to better connect with your inactive audience.

How to calculate it

Here’s the formula for calculating the re-engagement rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

Then, follow these steps.

For example, let’s say during the first quarter, 500 subscribers were identified as disengaged and sent a re-engagement sequence. At the end of the quarter, 100 of those had re-engaged.

Re-engagement Rate = (100 / 500) x 100 = 20%

In this example, the re-engagement rate is 20%, meaning 20% of previously inactive subscribers let you know they want to continue hearing from you.

How to improve the re-engagement rate

Apart from reducing the number of subscribers who become disengaged, there are several tactics you can use to encourage lapsed subscribers to re-engage.

Re-engagement relapse rate

What is re-engagement relapse rate?

This is the percentage of subscribers who, at one point became engaged as a result of a re-engagement campaign — but they’ve since become disengaged again.

Those who become disengaged again are called relapsed subscribers.

Why it matters

This metric can help you understand the effectiveness of re-engagement campaigns.

A high relapse rate could indicate that your re-engagement campaign isn’t addressing the actual cause of disengagement. For instance, people reading emails in preview mode which isn’t registering as engagement.

If you’re re-engagement campaign offers an incentive to remain on your list and the subscriber relapses, that incentive hasn’t solved the problem. Just delayed it.

On the other hand, a low relapse rate would be more positive, showing that your re-engagement efforts are effective in retaining previously disengaged subscribers.

This is an excellent metric to monitor because it can help you identify which re-engagement tactics work and which ones have flopped.

How to calculate it

Here’s the formula for calculating the re-engagement relapse rate.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then follow these steps.

For example, if you reengaged 1,000 subscribers and 150 of them lapsed again, the re-engagement relapse rate would be:

Reengagement Relapse Rate = (150 / 1000) x 100 = 15%

How to improve re-engagement relapse rate

It’s important to understand why a subscriber who previously re-engaged has become disengaged again.

Re-evaluate your re-engagement sequence. Are you delivering on your promise? Did you offer an incentive or offer? Did the reader only re-engage to take advantage of that incentive?

It’s important to understand why subscribers are becoming disengaged in the first place as this will likely be the reason they relapse.

Revenue metrics

The metrics in this section help manage the financial contribution a list makes. Is the email list paying for itself? What’s the average revenue generated per subscriber? How much does it cost to acquire a new subscriber?

The results from these metrics help you manage the cost of email marketing and ensure that subscribers are generating sufficient revenue to make email marketing a viable marketing channel.

These metrics can be unreliable but that comes from not taking into account the true costs involved.

Let’s look at revenue metrics.

Overall return on investment (ROI)

What is overall ROI?

It represents the financial viability of email marketing. It helps understand the amount of money being earned back.

Why it matters

Any organisation needs to know that the money spent is returning value.

ROI is an indicator of the value returned.

Knowing the ROI:

helps evaluate the effectiveness of an email marketing strategy
helps evaluate the effectiveness of campaigns
helps justify marketing budgets
guides decision-making
ensures that email marketing contributes positively to an organisation's success

How to calculate it

Here’s the formula for calculating the return on investment.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more accurate results, gather these numbers for a defined timeframe.

Then follow these steps.

For example, let’s say the revenue from email marketing was $100,000. The total cost of email marketing was $2,000.

ROI = ((100,000 – 2,000) / 2,000) x 100 = 4,900%

In this example, the return on investment is 4,900%.

To put this another way, for every $1 invested in email marketing, $49 was earned.

How to improve return on investment

Generally, there are two ways to improve email ROI. Reduce costs or increase revenue.

Reducing costs. This isn’t always a sustainable option. It can be counterproductive.

Increasing revenue. This can produce better results depending on the tactics used.

Better email marketing ROI is the outcome of improving other email marketing metrics.

Revenue per campaign (RPC)

What is revenue per campaign?

This metric represents the profitability of a specific email marketing campaign.

Why it matters

It’s a key indicator that measures the relative financial impact of a specific email marketing campaign.

When RPC results are compared amongst campaigns, it can help you understand which types of campaigns are more effective. For instance, a pre-holiday email campaign compared to a post-holiday email campaign.

How to calculate it

Here’s the formula for calculating the revenue per campaign.

Here’s a step-by-step explanation of the formula.

For this formula, three pieces of information are needed.

Then follow these steps.

For example, let’s say you sent 20,000 emails and 100 bounced. That’s 19,900 emails that were delivered.

That campaign generated $100,000 in revenue.

Revenue Per Campaign = (100,000 / (20,000 – 100)) x 100 = 502%
In this example, the open rate is 502%.

To put this another way, for every email delivered, $5 was earned.

How to improve revenue per campaign

Better revenue per campaign results are the outcome of improving other email marketing metrics such as open rate, click-through rate, and email conversion rate.

The average revenue per subscriber (ARPS)

What is average revenue per subscriber?

This is a dollar amount that represents the average revenue generated for each subscriber.

Why it matters

It gives an insight into how effective email marketing is in terms of generating revenue from the subscribers on a list.

It answers the question “Am I making enough money from my list?”

How to calculate it

Here’s the formula for calculating the average revenue per subscriber.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

Then, divide the total revenue by the number of subscribers.

For example, let’s say that the total revenue generated was $100,000 and there are 1,000 subscribers.

ARPS = 100,000 / 1,000 = 100

In this example, the average revenue per subscriber is $100.

How to improve average revenue per subscriber

Make sure your email marketing copy leads the recipient to the call to action and that call to action encourages readers to click. The email copy should highlight the benefits of selecting the CTA. Make sure the copy on the destination is written to convert them into customers.

It’s important that you’re attracting the right leads. If your product or service doesn’t meet the needs of your readers, you won’t get subscribers who generate revenue.

Make sure you have specific buyer personas. Understand your ideal customer and how your product or service can solve their problem. Marketing to your ideal customer will attract the right leads.

Existing customers can also be leads or advocates. Continue providing value to them. They may purchase again or encourage people they know to purchase from you. Consider a loyalty or referral program.

Subscriber lifetime value (SLV)

What is subscriber lifetime value (SLV)?

It’s the value of an email subscriber while they were active.

Why it matters

The longer a subscriber continues to purchase from you, the greater their lifetime value becomes.

It helps you identify subscribers that contribute the most revenue to your business. Using this information, you can create offers your highest spenders will love and keep them coming back for more.

If your list is growing but the SLV isn’t keeping pace, it may indicate that you’re not attracting qualified leads.

How to calculate it

Here’s the formula for calculating the subscriber lifetime value.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

Then multiply ARPS by ASL.

For example, let’s say the ARPS is $100 and the ASL is 1 year.

SLV = 100 x 1 = 100

The subscriber lifetime value is $100..

How to improve subscriber lifetime value

Make sure you’re attracting qualified leads. Make sure your marketing copy is written to attract your ideal customer.

Once you have a lead, your welcome sequence should educate the new lead about your business. Reinforce the problems that you solve, and how you’ve helped customers who look like your ideal customer.

Increase your average order value. Upsell related products or services. If a customer purchases one product, show them related products. If a customer purchases a monthly subscription, show them the value of an annual subscription.

For existing customers, create subscriber-only, limited-time special offers.

Subscriber acquisition cost (SAC)

What is subscriber acquisition cost (SAC)?

Shown as a dollar value, it represents the total cost of acquiring a new subscriber.

Why it matters

It gives insight into the financial impact of growing your email list.

If SLV is higher than SAC, then email marketing is a financially viable marketing channel.

How to calculate it

Here’s the formula for calculating the subscriber acquisition cost.

Here’s a step-by-step explanation of the formula.

For this formula, two pieces of information are needed.

For more meaningful results, gather these numbers for a defined timeframe.

Then, divide the number of subscribers gained by the total cost to acquire a new subscriber.

For example, let’s say you gained 2,000 new subscribers and the cost to gain them was $5,000.

SAC = 5,000 / 2,000 = 2.5

In this example, the cost to gain one new subscriber was $2.50.

How to improve subscriber acquisition cost

One tactic to improve SAC is to reduce costs. Evaluating costs associated with email marketing makes good business sense. Be mindful that reducing associated costs could reduce the effectiveness of email marketing. This could in turn affect list growth and average subscriber lifespan.

Understanding the relationship between SAC to SLV should lead to a focus on improving SLV rather than decreasing SAC.

Wrap up

Measuring and recording the most important metrics to you is crucial to improving your email marketing results.

While some metrics are considered inaccurate, trend analysis will give valuable insights into your subscriber’s reading behaviour as a group.

Most email marketing services will calculate the common metrics for you. Metrics such as open rate, click-through rate, unsubscribe rate, and bounce rate.

Now it’s time for some serious calculations!

Inbox Insights: Weekly email marketing tips, blog post and course updates delivered to your inbox. Sign me up.

Shane Herring

Combining 20+ years of technical education experience with 5+ years of email marketing experience, I bring unique skills to help you learn.

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