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Newsletter Metrics to Track: A Guide for Better Performance

Discover 11 essential newsletter metrics that media companies should track to enhance engagement and revenue. Learn how to calculate key metrics such as Open Rate, CTR, and Revenue per Subscriber, and get actionable tips on improving these metrics to drive better results for your newsletter

Jul 3, 2024

In this post, we'll explore essential metrics and how they can help you improve your newsletter's revenue-generating ability. You'll learn about their importance, how to calculate them, and tips to enhance them.

Stay tuned to discover how tracking the right metrics can drive better results.

Why You Should Be Tracking Your Newsletter Metrics

For media companies, tracking newsletter metrics helps you understand how well your content aligns with readers' preferences and how effectively you are meeting the expectations of your sponsors.

Metrics such as Open Rate, CTR, and Fill Rate allow you to gauge reader interest. With such insight, you can tailor your content to better meet your audience's preferences, leading to higher engagement.

For instance, a high Open Rate indicates that your subject lines and topics are compelling, while a high CTR suggests that your content and links are effectively driving further action.

Regarding sponsorship, tracking metrics like Revenue per Send and Fill Rates helps you understand the financial impact of your newsletter. It shows that you are maximizing the revenue from sponsored content.

A high Fill Rate indicates effective utilization of advertising space, making your newsletter a more attractive platform for current and potential sponsors.

Are you convinced about the importance of tracking your newsletter metrics? Then you'll like the following topic.

11 Newsletter Metrics to Track

It's time to explore 11 essential newsletter metrics to track, starting with Total Sends.

1. Total Sends

Total Sends refers to the total number of emails dispatched in each edition of the newsletter. It's calculated by simply counting all the emails sent out to the recipient list.

Monitoring Total Sends allows you to estimate the number of people your newsletter reaches. More importantly, this metric sets the stage for evaluating other indicators, such as open and click-through rates.

2. Open Rate

The Open Rate measures how many recipients open an email. To calculate it, divide the number of opens by the total emails sent, then multiply by 100 to get a percentage. This metric gauges the initial appeal of your email, primarily influenced by the subject line and pre-header text.

A high Open Rate often indicates that your email's subject has captured interest, enticing recipients to discover more about what you're saying.

Note that the accuracy of the Open Rate can be affected by certain limitations, such as image blockers, email previews, and aggressive spam filters. These factors usually prevent the tracking pixel embedded in emails from firing, which means opens may not always be recorded accurately.

Moreover, Apple's Mail Privacy Protection hides users' IP addresses to make it harder for senders to track the opening of emails. Not to mention that some recipients use automation tools to manage their emails, which can also skew this metric by marking emails as read.

So, how could you counter these challenges and get a more accurate measure of your Open Rate?

You may, for example, complement your analysis with another indicator, like CTR, to gain a more precise understanding of the actual engagement with content.

In fact, analyzing a set of metrics instead of single ones is always a good choice. This provides a more comprehensive view of performance, uncovering insights that might be missed when focusing on isolated numbers.

The Open Rate helps you understand the effectiveness of your subject lines. If it's low, this may suggest that your emails are either not compelling enough to provoke interest or are getting lost in a crowded inbox.

To improve this metric, consider employing A/B tests with different subject lines to see what aligns best with your audience. Personalizing the content and optimizing the sending time based on when your audience is most active can also enhance open rates.

You might also conduct regular list clean-ups, removing subscribers who don't open, click, or interact with your emails after a few months of inactivity.

3. Unique Open Rate

The Unique Open Rate tracks the percentage of distinct recipients who open an email at least once, providing a clearer vision of how many individuals are engaging with your content. It's calculated by dividing the number of unique opens by the total number of emails sent, and then multiplying by 100.

Why is it a key newsletter metric to track?

Well, unlike the Open Rate, the Unique Open Rate excludes repeated opens by the same recipient, which can skew data and paint an overly optimistic picture of engagement.

However, the Unique Open Rate can also be influenced by image blockers and privacy settings, which might prevent the email from being tracked correctly. Can you see the importance of monitoring a set of metrics instead of only one?

To improve your Unique Open Rate, craft content tailored to your audience's interests. Personalize emails by considering user behavior and preferences to increase the likelihood of opening them. Regular testing and optimization of subject lines can also enhance this metric.

4. CTR

CTR, or Click-Through Rate, indicates the percentage of email recipients who click on one or more links within an email. It's calculated by dividing the number of clicks by the total emails sent and multiplying by 100.

It reveals how effectively your email content motivates recipients to take action, measuring the appeal of your links and CTAs.

A high CTR indicates that your content is guiding subscribers to desired actions, such as reading further content, registering for an event, or making a purchase.

On the other hand, a low CTR may point to issues such as unclear or unconvincing CTAs, poor link placement, or content that doesn't match your audience's interests.

To enhance your CTR, ensure your CTAs are clear and prominently placed within your email. They should stand out visually and textually, compelling recipients to click without hesitation.

Improving CTR also involves A/B testing different elements of your emails, such as the CTA button design, the wording of the links, and even the overall email layout.


CTOR, or Click-to-Open Rate, is calculated by dividing the number of clicks by the number of unique opens and multiplying by 100.

It's a newsletter metric you should track, as it provides insight into how engaging and compelling your email content and embedded calls-to-action are for those who have opened the email.

Not sure about the difference between CTOR and CTR? It's simple. While CTR indicates the percentage of recipients who clicked on a link out of all emails sent, CTOR focuses only on those who have opened the email.

This makes CTOR a more precise measure of the content's effectiveness after the email is opened, as it doesn't consider the impact of the subject line or other factors that might influence the initial open.

A high CTOR indicates that once your email is opened, the content successfully drives recipients to take the actions you've designed, such as clicking on links to articles, product pages, or special offers.

To improve this metric, align the content with the interests and needs of your readers, as understood from your segmentation data.

Each email should be visually appealing and easy to navigate, with prominent and persuasive CTAs. High-quality images and a clear, engaging copy help enhance the attractiveness of your email, encouraging more clicks.

6. Revenue per Subscriber

Revenue per Subscriber quantifies the monetary value generated from each subscriber. To calculate it, divide the total revenue of your newsletter by the number of subscribers.

This metric provides an understanding of the financial effectiveness of your advertisement efforts, offering insight into how well your emails convert subscribers' interest into revenue.

A high Revenue per Subscriber indicates that your newsletter is driving a significant financial outcome, suggesting that your audience is responsive to your calls to action and that your products or services resonate well with them.

To enhance your Revenue per Subscriber, attract high-value sponsors and ensure that sponsorship placements are highly visible and engaging.

Craft your content so that it aligns with your audience's and your sponsors' interests, creating an integration that adds value for both parties.

Moreover, regularly review and adjust your sponsorship rates based on performance data to maximize revenue.

7. Revenue per Unique Open

Revenue per Unique Open measures the revenue generated from each unique email open, showing how effectively each open converts into financial gain. It's calculated by dividing the total revenue attributed to an edition of your newsletter by the number of unique opens.

This metric focuses on the financial return from engaged readers rather than just the number of emails sent. A high Revenue per Unique Open indicates that your content is converting their attention into revenue.

To enhance this metric, ensure that your content is highly relevant and appealing to your audience, as well as aligned with the interests of your sponsors.

This can involve personalizing content based on reader preferences, optimizing sponsored content placement to be more eye-catching, and ensuring that your sponsorships add value rather than disrupt the reader experience.

8. Unsubscribe Rate

The Unsubscribe Rate gauges the percentage of recipients who opt out of your email list after receiving an email. To calculate it, divide the number of unsubscribes by the total number of emails sent and multiply by 100.

This rate demonstrates recipient dissatisfaction or disinterest, signaling issues in your email content, frequency, or relevance.

Note that a small number of unsubscribes is expected. However, a high Unsubscribe Rate may indicate that your emails do not align with your audience's interests or are perceived as too frequent or intrusive.

A low Unsubscribe Rate, in turn, typically suggests that your content is well-received and that your email practices are in harmony with subscriber expectations.

To minimize the Unsubscribe Rate, balance the frequency and relevancy of your emails. Always craft content aligned with your readers' interests and preferences, thereby ensuring they find value in your newsletter.

Moreover, provide options for adjusting subscription preferences, as subscribers may opt to receive fewer emails rather than none at all.

You could also collect feedback from those who unsubscribe to understand which aspects of your email strategy need adjustment.

9. CAC

CAC (Customer Acquisition Cost) measures the expense of acquiring new subscribers. It is calculated by dividing the total costs associated with marketing and subscriber acquisition by the number of new subscribers obtained.

Understanding this metric helps you evaluate the efficiency of your subscription acquisition strategies. If your CAC is high, it may indicate the need to optimize your marketing approaches.

To reduce it, improve the relevance and quality of your content to attract and retain subscribers more effectively. Additionally, optimize your subscription funnels to minimize friction and improve conversion rates.

10. LTV

Lifetime Value (LTV) helps you understand the total revenue a subscriber is expected to generate over the entire duration of their relationship with your newsletter. To calculate it, divide the average revenue per subscriber by the churn rate.

The churn rate, in turn, is calculated by dividing the number of unsubscribed by the average number of subscribers.

A high LTV indicates solid, lasting relationships with subscribers, reflecting the effectiveness of your content and engagement strategies. Conversely, when this metric is low, it might suggest a need to enhance the value and relevance of your content to retain subscribers long-term.

To improve LTV, deliver consistent, high-quality content that aligns with your subscribers' preferences. Also, consider offering exclusive benefits or access to premium content to encourage loyalty.

11. Fill Rate

Fill Rate refers to the percentage of available advertising or promotional space within your newsletters that is actually utilized. It's calculated by dividing the number of spaces filled—with ads, sponsored content, or promotional material—by the total available spaces, then multiplying by 100.

A high Fill Rate indicates that you are effectively monetizing your newsletter real estate, maximizing the potential revenue from each send. It suggests that your newsletter is an attractive platform for advertisers and that you successfully match available space with relevant promotional content.

Furthermore, with a high Fill Rate, the law of supply and demand comes into play, meaning you could even charge sponsors more, thereby increasing revenue.

Improving Fill Rates involves enhancing your newsletter's appeal to advertisers. To achieve this, boost subscriber engagement and grow your audience, as a larger, more engaged subscriber base is typically more attractive to advertisers.

Providing data and analytics demonstrating your newsletter's effectiveness for advertising can also help attract more advertisers.

Tracking Newsletter Metrics With Sponsy

Sponsy is a platform for managing sponsorships within different channels, including newsletters. It provides ad performance data to enhance metrics tracking and optimization, which is invaluable for newsletters that utilize advertising as a revenue stream.

Integration capabilities with various email service providers ensure you can pull in data seamlessly, facilitating the analysis.

For companies looking to streamline their advertisement operations, Sponsy automates workflows, thereby maximizing inventory use and simplifying processes like reminders and status updates. This saves time and helps in tracking metrics.

By leveraging Sponsy, you can also benefit from its CRM features, which help maintain detailed records of all advertisers and their histories. This data is helpful to make informed decisions that enhance reader engagement and revenue generation from sponsorships.

Read our post on CRM for media companies to explore how integrating CRM with your email campaigns can further optimize your operations.


1. What are the most important newsletter metrics to track for engagement?

Key metrics for measuring engagement include Open Rate, CTR (Click-Through Rate), and CTOR (Click-to-Open Rate). They help you understand how effectively your content captures and retains audience attention.

2. How can I improve my newsletter's CTR?

To improve CTR, craft compelling CTAs, personalize your content, and test different designs and timings. Also, ensure that your emails are relevant and appealing to your audience.

3. What does a high Unsubscribe Rate indicate about my newsletter?

A high Unsubscribe Rate often indicates that your content may not be resonating with your audience or that your emails are too frequent. To address this issue, consider reviewing content relevance and email frequency.

4. Why is Fill Rate important for my newsletter?

Fill Rate measures the percentage of available advertising space in your newsletter that is actually utilized. It helps you gauge the attractiveness of your newsletter to sponsors and optimize your monetization strategies. Monitoring and optimizing it ensures you are not missing out on potential sponsorship revenue.

5. Why should CAC and LTV be the core metrics of your newsletter?

If CAC is lower than LTV, you are spending less money acquiring a subscriber than they generate—which is excellent. On the other hand, if CAC is greater than LTV, you are spending too much to bring subscribers to your newsletter, indicating that you should improve your monetization and retention strategies.

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