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Erin · 23 min read · Tips and resources · June 8, 2021

7 essential email marketing metrics and how to improve them

When you travel down the email marketing road, there is no fast lane. Developing a winning email strategy takes time and every campaign is a learning experience. So enjoy the drive and remember to celebrate the little wins along the way.

While it’s true that industry benchmarks can provide some insight into how your emails are performing, no one else in your industry is producing the same content as you or delivering it to the same subscribers.

Comparing your own metrics to those industry standards can give you context, but it’s more important to focus on improving your own email campaigns. By tracking the right email metrics, you can slowly make small changes and optimize your email campaigns.


Email marketing metrics are the key performance indicators (KPIs) that help measure the performance of email marketing campaigns. The purpose of email marketing KPIs is to provide the stepping stones that ultimately lead you to a high-level goal. 

For example, your marketing objective might be something like: “I want to grow my customer base by 20% this year”. Achieving such a high-level goal isn’t a 1-step process. Email marketing KPIs like open rates and click-throughs allow you to measure your email performance and set short-term goals that will lead you to where you want to go.

It's important not to focus on just one or two KPIs, but to look at a range of metrics to ensure all aspects of your email campaigns are working well. Most email service providers like MailerLite track email marketing metrics and display them on your dashboard and campaign reports.

Email marketing metrics campaign report - MailerLite dashboard

You can also use these metrics in conjunction with other marketing tools such as Google Analytics to track your entire digital marketing performance.

In this article, we’ll show you the 7 most important email marketing metrics that you should be tracking to elevate your email marketing.


Email open rate measures the percentage of campaign recipients who open your campaign. Monitoring your open rates gives you a solid indication of how well your campaigns are doing with a specific demographic. If your open rate is high, it suggests your past emails (and subject lines) are resonating with your target audience.

In MailerLite, you can find your individual campaign open rates in your Sent folder, as well as in your campaign reports and your dashboard.

Email marketing metrics - campaign report in MailerLite dashboard

How to improve open rates

A/B test subject lines

A/B testing is a method of determining which of two email campaigns will perform better. When creating an A/B split campaign, you can change one variable, such as the email subject, to see which approach gets the best open rate.

Include numbers in subject lines

Much like blog posts, email subjects that include a number yield higher open rates. Just make sure you deliver on your promise. If your subject line is “5 ways to design a bedroom on a budget” make sure that you actually provide 5 examples.

Personalize your sender address

Put a human face on your emails by personalizing the sender address. For example, setting your sender name as “Blair from Interior design co.” and your sender address as “blair@interiordesign.co” is a far more personal experience than “Interior design co.” and “noreply@interiordesign.co”.

Add an email preheader

Preheader text is the preview text that appears after your email subject line in the inbox. It gives subscribers a further idea of what to expect inside. One engaging sentence can be the difference between someone opening or not opening an email.

Check out this blog post to learn more about how to increase your open rate with email preheaders.

Use auto-resend campaigns

This powerful premium feature allows you to set up a campaign that will automatically resend to those who didn’t open it after a selected amount of time. You can even set it up so that the auto-resend has a different subject line so that subscribers don’t feel bombarded.


Another metric you may already be familiar with is your click-through rate, also known as “click rate” or simply “CTR”. Your CTR measures the number of unique clicks on your campaign per the number of subscribers. If your click rate is high, it means the email content is compelling and your call-to-action (CTA) is strong.

In MailerLite, you can find the CTR of each individual campaign displayed in your Sent folder, as well as in your campaign reports. You can find your monthly CTR on your Dashboard page.

Premium users can also switch on click maps, so you can see where most of your subscribers are clicking within your email campaign.

Example of click-through rates displayed on a click map in MailerLite

Note: The click-through rate is measured against the total number of sent emails, not just those that were opened. To learn more about calculating your click-to-open rate, jump down to number 6.

How to improve your email click-through rate

Segment your subscribers

Email segmentation is the practice of dividing your email list into different groups. In email marketing there’s no such thing as a one-size-fits-all newsletter, so segmenting your list based on different factors will help you improve email engagement. The more relevant your email content is to your audience, the more likely they will continue to interact with it. 

Segment your subscribers the moment they sign up for your newsletter by including interest groups inside your forms.

Or, if you want to learn more about your existing subscribers and their interests, try including a survey block in your newsletter. You can use their answers to split subscribers into smaller, targeted groups.

Design a campaign with interactive content

Along with embedded surveys and quizzes, MailerLite offers a variety of interactive email blocks specifically designed to engage subscribers including article blocks, video blocks, embedded social media posts, various e-commerce blocks, and even an RSVP block.

Take the article blocks for example: Instead of giving away all the info you have to offer in your newsletter, you can tease your subscribers with an excerpt from a longer article on your website.

Example of article blocks in MailerLite drag and drop editor

You’re not restricted to using purpose-built interactive email blocks to create interactive content. Check out this article on how to use interactive content in your newsletters to boost engagement for more examples of engaging content.

💡Tip: Send test emails

Keep in mind that different email clients format your newsletters differently. Test your campaigns with multiple email clients to make sure all your readers can engage with your content.

Provide sharing options

There are 2 options you can give your subscribers when it comes to sharing your newsletter. Social sharing or forwarding to a friend.

If you use the MailerLite drag & drop editor, you can include social share blocks in your newsletter content or footer. These blocks include sharing links to popular social media platforms such as Facebook, LinkedIn, and Twitter, as well as a forward button through our forward-to-a-friend feature.

Add a P.S section

P.S sections are often used by email marketers as a way to add an additional remark at the end of a message. A final, punchy thought to get the reader thinking. You should utilize the P.S. to draw attention to aspects of your offer that you believe the subscriber will be interested in. 

Take this MailerLite newsletter for example:

MailerLite newsletter P.S example Meg rounded profile signature

The newsletter features an article about email automation triggers, then goes on to talk about behavioral segmentation with automation. In the end, Meg rounds off the newsletter with a reminder that we offer a complete guide to email automation for beginners.

While most clicks happened at the first call-to-action (CTA), 148 people who might not have otherwise clicked, were enticed by Meg’s P.S.

Create a CTA that works

Speaking of CTAs, including a strong call-to-action in every newsletter is guaranteed to improve your click-through rates.

A call-to-action is a critical element in any good email campaign that serves as a guide for the reader on what to do next. In order for a CTA to be effective, the narrative laid out in your newsletter needs to have reached a climactic point before the CTA is added.

Let’s take another look at Meg’s newsletter:

MailerLite newsletter CTA example blue button

Before the CTA, Meg has given readers a teaser of all the amazing things they can achieve with email triggers, but they’ll only get to find out what they are and how to use them by clicking the CTA. 

Check out our ultimate guide on how to create a CTA that works for more great examples.

More tips to improve your click-through rate

Your bounce rate refers to the number of subscribers who didn’t receive your campaign due to their email addresses being invalid or otherwise undeliverable.

When tracking your bounce rate, it’s important to understand the difference between hard and soft bounces. The short version? Soft bounces are temporarily undeliverable whereas hard bounces are permanently undeliverable.

If you’re using MailerLite, you can find a campaign’s individual bounce rates in your campaign report.

If you have a high bounce rate, your reputation as an email sender is at risk. Once your reputation is damaged, your emails will start automatically landing in the spam folder. 

So monitoring your bounce rates and managing your email list accordingly will help you to maintain a good sender reputation and optimize your email deliverability.

How to improve bounce rates

Validate your email list

Take the guesswork out of culling invalid email addresses from your subscriber lists by using an email validation tool. You can test and remove invalid addresses from your email list without harming your sender reputation.

Use permission-based (opt-in) email lists

The best way to avoid bounces is by only sending your quality content to people that asked for it. The beauty of email marketing is that your subscribers like you, and like what you have to say.

If you’re just starting out, purchasing an email list might be tempting, but trust us when we say it’s simply not worth it. Purchased email lists more likely to be riddled with invalid email addresses. As a result, your bounce rate will increase over time.

Instead, take the time to learn why purchasing an email list is a huge mistake and gather info on building a genuine list.

​👉 Bonus tip

Enable double opt-in on your email signup forms so that subscribers confirm their subscription in a confirmation email. This prevents “bots” from being added to your email list.

Avoid free email domains

If you use a free email domain like "@gmail.com," the chances of having your email flagged as spam increase dramatically. As a result, your email marketing reputation will be tarnished, which in turn leads to a rise in email bounce rates.

Instead, use a professional email address that matches your domain name. Then improve your deliverability even further by authenticating your domain.


Spam complaints refer to the number of subscribers that reported any of your campaigns as spam. In MailerLite, you can find individual campaign spam complaints in your campaign reports, and your monthly spam complaints on the dashboard page.

Spam complaints may seem like a scary topic. But they’re simply a part of email marketing. And eventually, even the most cautious marketers can receive spam complaints.

Keeping an eye on your spam rate gives you insight into the quality of your subscriber list and the consistency of your content.

How to reduce the risk of spam complaints

Avoid using old subscriber lists

When you re-use an old email list after a period of not contacting those subscribers, chances are more than a few of those contacts aren’t going to remember signing up to receive your newsletters.

If under a year has passed since you last contacted this subscriber list, you can invite those contacts to opt in again. You can send a campaign reminding subscribers who you are when they signed up, and let them know what kind of content to expect if they re-opt-in. 

Keep your content consistent

Sending newsletters that cover multiple topics to your entire list can confuse subscribers and lead them to feel like they’re not getting what they signed up for. Keep your content consistent to avoid spam complaints from your subscribers.

If your business relates to more than one topic, segment your subscribers based on their interests. You can also utilize dynamic content blocks so that subscribers all receive the same newsletter, but only see the content that’s relevant to them.

Include a visible unsubscribe link

All marketing emails must include an unsubscribe link somewhere in the email content. The best and most common place for this link is in the email footer.

Unsubscribe link example - MailerLite drag and drop editor

If a subscriber can’t find your unsubscribe link, their only choice is to mark your email as spam.


The unsubscribe rate is the number of campaign recipients that have unsubscribed to any of your campaigns. A high unsubscribe rate suggests that some aspects of your approach are weak (subscriber segmentation, subject matter, email frequency) and you should examine your email campaigns more closely.

In MailerLite you can analyze the unsubscribe rate of individual campaigns in your campaign report, and your monthly unsubscribe rates on the dashboard page.

Tips to improve your unsubscribe rate

Avoid sending too many emails (if you don’t have to)

Contrary to popular belief, there’s actually nothing wrong with sending 7+ newsletters per week, as long as you have something valuable to say. When it comes to email marketing, quality beats quantity every time. If you’re pumping out shallow newsletters that don’t offer much value, your subscribers are more likely to jump ship.

So don’t send email campaigns for the sake of pushing out content. Remember, the number of emails you send doesn’t matter as long as you find a rhythm that allows you to craft emails people care about.

Check out our email frequency data analysis in this article on email cadence.

Use interest groups inside forms

Deliver relevant email content from day 1 by using interest groups inside forms. When you add interest groups to your forms, subscribers can self-select which groups to which they’d like to be added.

You can use interest groups to find out which topics subscribers are most interested in hearing about, or even how often they’d like to receive updates.

Interest groups in MailerLite drag and drop editor

If subscribers are receiving the information they asked for, exactly when they ask for it, they’re more likely to stick around and continue reading your newsletters.

Optimize your unsubscribe page

The unsubscribe page contains a survey that is an excellent tool to learn why your subscribers leave and how to fix it.

Unsubscribe page example black and white why you unsubscribe feedback

Unsubscribe surveys give you the information you need to rethink and improve your email content. You want to make sure your new subscribers are satisfied and stay on your email list as you grow.


Your click-to-open rate (CTOR) is the percentage of subscribers who opened your newsletter and also clicked a link inside it. It’s calculated by comparing the number of subscribers who clicked a link in your campaign with the number of subscribers who opened it.

CTOR formula = unique clicks divided by unique opens x 100 - MailerLite

CTOR is a useful metric for determining how engaging your material is for your subscribers. Your readers are more likely to click through to discover more if your links, layout, copy, and overall content are appealing.

Calculating your CTOR

The formula to calculate your CTOR is unique clicks / unique opens x 100. Multiplying by 100 allows you to convert the result into a percentage out of 100.

For example 678 unique clicks / 2512 unique opens x100 = CTOR 26.9%.

You can simply type your formula into a search engine, or use an online CTOR calculator.

You can improve your CTOR by implementing the same practices you would use to improve your overall click-through rates, with: Subscriber segmentation, engaging content, sharing options within your newsletter, including a P.S section and creating great CTAs.


A conversion is when a website or landing page visitor completes a desired action, usually in response to a call-to-action. For example, when someone downloads a freebie or signs up for your newsletters.

While “traffic” measures how many people visit your website or landing page, conversion rates measure what visitors do once they get there.

Your conversion rate is a good indicator of what kind of content resonates with your website visitors, and every successful marketing plan is built around this critical marketing metric.

In MailerLite, you can find your individual form conversion rates on the Forms and Sites pages. It’s valuable to measure your form conversion rates against each and ask yourself why one form or landing page is performing better than the other? 

Tips to improve conversion rates on your forms and landing pages

Highlight your objective

Since the purpose of a lead magnet or landing page is to have visitors complete a single action,  it needs to be clear what that objective is. Write a clear headline that highlights your offer. 

Follow up with a description of what your offer is and why potential customers will benefit from signing up for, downloading or purchasing your offer and a strong, visible CTA.

Landing page example the world of abstract art book clear CTA button

Discover more landing page inspiration when you check out these 11 tips on building effective landing pages.

Remove distractions from landing pages

Remember, you have a whole website to advertise the rest of your products or services; your landing pages should be dedicated to that one must-have offer.

You don’t want your visitors to become distracted and abandon your landing page before they’ve completed the action you want them to take.

MailerLite offers a variety of templates to help you design your landing pages.

Place signup form strategically

When it comes to successful form conversions, the placement of your signup form is perhaps one of the most important elements. Essentially, you want to put your form somewhere everyone can see it.

Common places to embed an email signup form
  • Footer (bottom of the page)

  • Sidebar

  • Within a blog post

  • As a floating bar

There are some great examples of creative signup forms  in this article on how to optimize your email signup forms.


The thing is, that’s entirely up to you. The answer to this question is unique to your business and is based on a number of factors, including what industry you’re in, the goal you're trying to accomplish (sell products, drive traffic to your website, create brand awareness) and whether or not email is your main form of communication with your customers.

Tracking the right metrics for your business provides the insight you need to optimize your marketing efforts.

The best approach to experience real improvement is to break the process down into 3 steps:

1. Establish a benchmark

It's helpful to develop a baseline before making any adjustments. For example, if your goal is to get more people to read your newsletters, find out how many subscribers are already opening your email campaigns.

Once you have an idea of how your campaigns are performing, you can begin to set incremental targets for yourself.

2. Determine who your target audience is

A well-defined target audience is the foundation of your email marketing strategy. If you cast your net too wide you risk missing out on creating deeper, meaningful relationships with the people who are most interested in your products or services.

3. Test, tweak and test again

Email campaign optimization is a journey, not a destination. Making small adjustments and testing them over time is the best route to take when working to improve your metrics. There’s no need to flip your strategy on its head all at once. If you make too many changes in the beginning, it’ll be harder to tracker whether or not your changes are helping. 

Test small changes at a time, and enjoy the ride. 🚗


Erin Ford

I’m Erin, I write content here at MailerLite. When I’m not typing away at my laptop, pumping some low-fi jams, you can find me at the nearest beach with my furry little rescue pooch, Alfie.