Understanding Email Marketing Metrics

Melanie Balke
March 26, 2024

Few things are as important to your marketing strategy as your metrics. They may look like numbers on a computer screen, but those pixels dictate your marketing success!

Unfortunately, there are more than a few marketing metrics. There are more than a few dozen metrics. It’s almost impossible to count every conceivable email marketing metric, and doing so would be a waste of everyone’s time. After all, what you’re really after is their meaning.

What do those numbers mean? How do they affect your email marketing campaigns?

Keep reading! This blog post is dedicated to explaining the ins and outs of email marketing metrics. I’ll explain those must-know metrics and how they reflect the health of your marketing strategy.

Email Marketing Metrics and Key Performance Indicators

I’ll start by mentioning key performance indicators (KPIs). These handy metrics are a collective measurement of your campaign success. Though they may seem like scattered data points, they form a cohesive picture in the hands of a professional.

5 Must-Know Email Marketing Metrics

A chessboard. "Email Stats: 5 Marketing Metrics to Know."

Different businesses will have different KPIs. Your most important metrics ultimately depend upon your goals, and they may even vary from one campaign to the next!

While I can’t say what your most important KPIs will be, I can outline some of the most important metrics in general.

1. Bounce Rates

In email marketing, a “bounce” is when an email fails to reach its recipient’s inbox.

There are two types of bounces:

  • Hard bounces are the most harmful. These are unavoidable and permanent blockades against your email marketing campaigns.
  • Soft bounces are more common. These temporary problems are often caused by problems with internet service providers and individual user accounts.

Logically, that means your bounce rate is a measurement of how often these events happen.

A high bounce rate indicates a technical problem with your email marketing strategy. One of the most common causes of this problem is a proliferation of invalid email accounts. However, inadequate list hygiene and a poor deliverability rate may also be culprits.

Whatever the case may be, your bounce rate matters! While it’s little more than one of many email analytics data points for you, it’s an essential indicator for your email service provider. A consistently high bounce rate is a red flag that often results in widespread blacklisting. (Yikes!)

How to Find Your Email Bounce Rate

Most email marketing platforms track metrics automatically. Your bounce rate will be tallied behind the scenes and presented as a nice, round percentage. However, you don’t need a supercomputer to calculate it!

It’s a simple two-step process:

  1. Divide the number of bounced emails by the number of emails sent. For example, if 600 of your 1,500 emails bounced, you’ll divide 600 by 1,500. The result will be 0.4.
  2. Multiply the product by 100. Continuing from the example, you’ll multiply 0.4 by 100 and get a 40% bounce rate. Uh-oh!

You want a low bounce rate. Otherwise, you’re wasting money on campaigns that never reach your target audience.

Most marketers follow a simple rule: If an address yields a hard bounce, remove it! After all, you won’t get any customer engagement from bounced emails.

2. The Click-Through Rate (CTR)

Also known as a CTR, your click-through rate may just be the most important metric to know.

This metric measures how many subscribers open and act upon your email marketing campaign.

In some ways, your click-through rate is an extension of your open rates. However, its specificity negates many of the problems posed by modern open rates. It subverts the privacy-driven automation that plagues Apple Mail users and offers a more cohesive view of your subscriber engagement metrics.

Now, don’t misquote me! I’m not telling you to ignore your open rates. That age-old metric remains an important marketing touchstone. However, recent changes — many driven by an understandable desire for consumer privacy — have rendered email marketing’s perennial darling an unreliable narrator. The problem has only grown as people flock to mobile devices.

This newfound instability has driven many marketing professionals to embrace a compare-and-contrast approach to marketing metrics. While the open rate remains an invaluable companion metric to the deliverability rate, it must also be considered against a brand’s click-through rate.

How to Calculate Your Click-Through Rate

Again, you’ll use a two-part formula:

  1. Divide the total clicks on your call-to-action link by the number of emails sent. Suppose you sent 4,130 email campaigns. The number of subscribers is irrelevant. What matters is that you got 1,100 clicks on your call-to-action link. For the first step, you’ll divide 1,100 by 4,130, giving you (approximately) 0.27.
  2. Multiply the result by 100. Now, turn that number into a percentage. The example yields an impressive (and somewhat unrealistic) CTR of 27%!

As of 2021, the average click-through rate is 2.3%, which includes the industry average for every industry.

3. Conversion Rates

Your conversion rate is an even more specific engagement metric.

This number measures how many people opened your email and completed your desired action. In many cases, this target action is monetary. However, there are non-monetary conversions. Surveys and user-generated content submissions are two examples of such non-transactional goals.

Like your click-through rates, conversion rates are an extension of your deliverability rate and open rate. A customer cannot convert unless an email is successfully delivered and opened. It also builds upon your click-through rate!

Think of these four metrics as a pie. Your delivered emails form the entire pie, while your open rates are a (hopefully) healthily-sized portion of that pie. Take a slice from that part, and you have your open rate. A slice of that is your click-through rate, and a slice of that is your conversion rate!

How to Measure Your Conversion Rate

The conversion rate demonstrates a mix of positive traits.

A high conversion rate shows dedication to your craft. You achieve such a feat by maintaining customer loyalty and pruning out unengaged subscribers. Generally, outstanding conversion rates also correlate to a streamlined customer journey. Strive to minimize distraction and reduce the number of barriers between your subscriber list and your website traffic.

Then, measure your conversion rate with this two-step formula:

  1. Divide the number of completed actions by the total emails sent. Don’t mistake the second number for emails delivered, either! For this example, assume 200 actions came from 5,000 emails. 200 divided by 5,000 is 0.04.
  2. Multiply the result by 100. 0.04 multiplied by 100 is 4, so you have a 4% conversion rate. Nice!

4. Return on Investment (ROI)

Your return on investment (ROI) is your monetary stat. It measures the literal value of your email marketing strategy. Needless to say, you want it to be high!

However, your ROI measures more than your dividends. It reflects your strategy’s efficacy and, in many ways, the true breadth of your conversion rate. You can calculate unsubscribe rates all day — until you’re turning blue — but that won’t convince anyone at a budget meeting; your ROI will.

How to Calculate Your Return on Investment (ROI)

Don’t think like an email marketer. Instead, approach the metric as if you’re on the sales team. Forget about subscriber list size and number of emails delivered. Focus on the literal worth of your marketing emails.

Then, follow this three-step process:

  1. Subtract the income earned from your marketing campaign from your total expenditure. Assume a company spends $915 and earns $2,500. For the first step, you’ll subtract $2,500 from $915, giving you $1,585.
  2. Divide the product by your total expenditure. For the example, you’ll divide that $1,585 by $9915. The result is approximately 1.73.
  3. Multiply the result by 100. Finally, turn that number into a percentage. In the example, 1.73 multiplied by 100 is 173. That means you had an extraordinary 173% return on investment!

5. Unsubscribe Rates

Finally, your unsubscribe rate is a self-explanatory concept. This email marketing metric measures, among other things, the personal worth of your campaigning. Many marketing pros use unsubscribe tallies to analyze site usage and pinpoint potential gaps in a brand’s email marketing strategy.

However, on its own, the unsubscribe rate is a simple metric. It measures (as you probably guessed from its name) how many subscribers leave your list.

And don’t try to artificially lower the number by hiding your unsubscribe link! That’s a literal crime!

Why the Unsubscribe Rate Isn’t Your Enemy

Now, it sucks to have a higher-than-expected unsubscribe rate. Across all industries, the average unsubscribe rate currently hovers around 20%. That seems high!

However, those departing users are no longer interested in your content. They’ve lost value as email recipients, and their continued presence is actively damaging your email performance.

As the old saying goes, quality matters more than quantity. It feels nice to say you have a 15,000-strong subscriber list, but that means nothing if 14,999 of those email recipients don’t care about your emails! (Well… It does mean one thing. It means you’re buying some expensive spam complaints!)

That said, you still don’t want a high unsubscribe rate. Abnormal spikes in this email metric usually indicate an internal or strategic problem. Some common causes of unexpected unsubscribe rates include:

  • A broken or unclear sign-up form (meaning you may need to consider double opt-in)
  • Fewer active subscribers
  • Frequent low-quality campaigns (e.g., broken landing pages, missing images, and dead-end links)
  • Lack of relevant content (often remedied with some A/B testing)
  • Misguided marketing efforts (often caused by a stagnating email marketing program)
  • Misleading or confusing subject lines
  • Poor list hygiene
  • Poor standing with email service providers

How to Calculate Your Unsubscribe Rate

Think of your unsubscribe rate as a frog or salamander. It’s an indicator species. Consistent performance means you’re doing well and have a healthy email marketing “ecosystem.” A sudden change is cause for concern.

The formula is a two-step process:

  1. Divide the number of users who unsubscribed by the total number of emails sent. Again, don’t confuse that second figure with the number of emails delivered. For this example, assume a brand lost 50 subscribers after sending 300 emails. 50 divided by 300 is approximately 0.17.
  2. Multiply the result by 100. In the example, 0.17 multiplied by 100 is 17, so you have a 17% unsubscribe rate.

Yes, you can do the opposite to calculate your list growth rate. Just use the number of new subscribers.

Why Your Email Marketing Metrics Matter

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Regardless of the specifics, all your email marketing metrics are essential.

Each number is a reflection of your email marketing.

That spam complaint rate reflects the efficacy of your email strategy. That low click-to-open rate may be the first sign of mass disinterest. A sudden drop in your deliverability rate is a problem!

Your email analytics matter, and ignoring those numbers will impact how well your campaigns perform.

However, the real problem is cohesion. Everyone can see email metrics, but few can understand how they interact. To many, a low conversion rate and a high open rate are separate issues. Those email marketing metrics are too often misunderstood as individual parts of email campaigns. To a skilled email marketer, they’re symptoms of the same problem.

For the best results, you need a team that understands the interplay of your email marketing metrics. You need a business partner ready to tweak every subject line to perfection.

You need experts, and it sounds expensive.

That’s why I founded The Email Marketers!

My team of hand-picked professionals understands the complex world of marketing emails. They’ll work alongside your business to amplify every metric, from email deliverability to conversion rates. They’ll deliver results tailored to your needs, not some “other guys’.”

It’s time for you to join the action.

Get better email subject lines, and let us handle your future emails. Consistency, quality, and performance are just a few reasons clients love The Email Marketers. Schedule a free strategy session and find your own!