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Email Marketing KPIs


Why are email marketing KPIs that important?

Email marketing KPIs serve to measure, compare and quickly classify the performance of your emails.

Using Email Marketing KPIs allows you to:

  • identify strengths and optimization potentials of your emails,
  • make future campaigns more successful,
  • and quickly assess whether you have achieved your email marketing goals.



What are the most important Email Marketing KPIs?

The most important key figures in email marketing include:

  • Delivery Rate
  • Opening Rate
  • Click Through Rate (CTR)
  • Unsubscribe Rate
  • Bounce Rate
  • Spam Rate
  • Conversion Rate


What are the formulas for email marketing KPIs? What do they indicate?

1. Delivery Rate:

The delivery rate indicates what percentage of the recipients actually received the email. It reflects how good the quality of the recipient lists is. The delivery rate is calculated as follows:


Delivery Rate = (Number of Recipients – Bounces) / Number of Recipients * 100



The online shoe shop ProShoe has a total of 100,000 email recipients. 70,000 of them are female. As part of a marketing campaign, ProShoe wants to inform all women about the new women's collection and sends an email newsletter to 70,000 newsletter subscribers. However, the email does not reach 1,000 recipients. ProShoe thus achieves a delivery rate of 98.5%. (Delivery rate = (70,000 recipients - 1,000 bounces) / 70,000 recipients * 100 % = 98.5 %)

This is a good figure, which is roughly in line with the industry average. ProShoe can therefore be satisfied with their delivery rate.



2. Opening Rate:

Another important email marketing KPI besides the delivery rate is the opening rate. It shows how many percent of the recipients have actually opened the email. A distinction is made between total openings and unique openings. While all openings are counted in the case of total openings, the multiple openings of a person are ignored in the case of unique openings.

The unique opening rate is calculated as follows:


Unique Opening Rate = Unique Openings / (Number of Recipients - Bounces) * 100



ProShoe distributes a newsletter about sandals to all 15,000 recipients, for whom the online shop has found out with the help of link tagging and targeted surveys that they are generally interested in sandals. Of the 15,000 recipients, the email is actually delivered to 14,750. 3,700 people have opened the email at least once. The unique opening rate is therefore 25.1%.

(Unique opening rate = 3,700 unique openings / (15,000 recipients - 250 bounces) * 100 = 25.1 %)

A value of 25.1% is above average for online shops. However, other sectors show opening rates of 30% and more.


How can you improve the opening rate?

The opening rate is influenced in particular by the subject line, the sender, the preview text and the time of delivery.

  • Perform subject line tests.
  • Test different sender addresses.
  • Perform A/B tests or multivariate tests. However, be sure to change only one variable at a time to find out which variables perform best.
  • Send your emails at the best individual time using ProCampaign® Best Send Time Optimization. This ensures that the email is high up in each recipient's inbox and is more likely to actually be opened.



3. Click-Through Rate

The click-through rate is the percentage of people who clicked on at least one link of the email. The click-through rate is calculated as follows:


Click-Through Rate = Number of Unique Clicks / Number of Unique Openings * 100



ProShoe sends a newsletter to 10,000 recipients who have an affinity for ballerinas due to their behavior and their analyzed interest. Of the 2,500 people who actually opened the email, 300 clicked on the link to the new Ballerina collection on the ProShoe website. The click-through rate of ProShoe is therefore 12%.

(Click-Through-Rate = 300 unique clicks / 2,500 unique openings * 100 = 12 %)


How can the click-through rate be increased?

  • Encourage your recipients to take action.
  • Use Call to Actions that are different in color from the rest of the content.
  • Carry out A/B or multivariate tests and change the content of your call to action.
  • Use countdowns to create a sense of urgency and encourage your recipients to take targeted action.



4. Unsubscribe Rate

Another important indicator for the quality of your email marketing is the unsubscribe rate. It indicates the percentage of recipients who unsubscribed from the newsletter by clicking on the corresponding link. The unsubscribe rate is calculated as follows:


Unsubscribe Rate = Number of Unsubscriptions / (Number of Recipients – Bounces) * 100



ProShoe sends an email newsletter to all 15,000 men who have already ordered at least one pair of sneakers from the ProShoe Online Shop. Of all recipients, 14,500 have actually received the email and 70 have unsubscribed from the newsletter. The unsubscribe rate is therefore 0.48%.

(Unsubscribe rate = 70 unsubscriptions / (15,000 recipients - 500 bounces) * 100 = 0.48 %)

As a first measure to find out why the unsubscribe rate is that high, ProShoe introduces a landing page that asks recipients for their reason for unsubscribing after clicking on the unsubscribe link. ProShoe uses this information to improve the quality of the email newsletter and thus reduces the unsubscribe rate.


How can you reduce the unsubscribe rate?

  • Allow your recipients to determine the maximum frequency of emails sent.
  • Offer the possibility to receive information only on specific topics.
  • Ensure high quality content. Quality usually takes precedence over quantity.
  • Check the display of your emails on mobile devices. The template of your emails may have to be adapted.



5. Bounce Rate

The bouncerate shows the percentage of emails that could not be delivered. A distinction is made between hard and soft bounces. Hardbounces are permanently unreachable recipients, while softbounces are only temporarily unreachable (e.g. because their mailbox is full).

The bounce rate is calculated as follows:


Bounce Rate = Bounces / Number of Recipients * 100



ProShoe sends an email newsletter about boots to 10,000 selected recipients. A total of 400 emails could not be delivered, 100 due to hardbounces and 300 due to softbounces.

The total bounce rate is therefore: 4%.

(Bounce Rate = 400 bounces / 10,000 receivers * 100 = 4 %)

The hardbounce rate is: 1 %.

(Hardbounce Rate = 100 Hardbounces / 10,000 recipients * 100 = 1 %)

The softbounce rate is: 3 %.

(Softbounce Rate = 300 softbounces / 10,000 receivers * 100 = 3 %)


Hardbounces in particular are important criteria. If the hardbounce rate is permanently too high, the sender is declared as spam by the email clients.



6. Spam Rate

The spam rate shows the percentage of recipients who have "marked the email as spam" or the email has already been sorted out by spam filters. It is calculated as follows:


Spam Rate = Number of Spam Markings / Number of Recipients * 100

The spam rate is a very important indicator, as the probability that future emails from the same sender will be rejected or marked as spam is very high.



ProShoe sends 5,000 emails to all recipients who have not made a purchase for more than a year and have not opened the emails of the last three months. 10 recipients mark the email as spam. The spam rate is therefore 0.2%.

(Spam rate = 10 spam markings / 5,000 recipients * 100 = 0.2 %)


What can you do to reduce the spam rate?

To reduce the spam rate, these measures are suitable:

  • Verify your domain(s) and send your emails via a dedicated IP address.
  • Do not use noreply@ email addresses.
  • Avoid spam words.
  • Write appealing subject lines.
  • Send high quality content.
  • Do not buy email addresses from third parties, but build your own high-quality contact list.



7. Conversion Rate

The conversion rate shows the percentage of recipients who have performed a desired action. It is calculated as follows:


Conversion Rate = Number of Conversions / Number of Recipients * 100


What exactly counts as conversion depends on the company, industry and goal of the newsletter or email marketing.


For example, a conversion can be one of the following activities:

  • Purchase of a product in the online shop
  • Registration for an event
  • Whitepaper download
  • Participation in a sweepstake
  • Participation in a survey

In order to calculate the conversion rate, it is necessary that the systems (e.g. website, online shop, landing page, CRM tool, email marketing system) are integrated and that it is possible to identify exactly when a conversion took place.



ProShoe would like to find out more about their email newsletter subscribers and therefore sends an email to 50,000 selected recipients asking them to complete a survey which is used to query certain characteristics, interests and preferences of the respective consumer and which is stored in ProCampaign® as a basis for further selections. 5,000 people take part in the survey. The conversion rate is therefore: 10 %.

(Conversion rate = 5,000 survey participants / 50,000 recipients * 100 = 10 %)

ProShoe is very satisfied with this value.



Email Marketing KPIs give you a quick overview of the success of your email marketing. ProCampaign® offers detailed evaluations of your newsletter and helps you to identify and implement success factors and optimization potentials of your email marketing.

Curious to learn more?

We are happy to show you ProCampaign® via live demo!

For LLOYD, ProCampaign is a comprehensive e-mail marketing tool that can certainly keep up with the solutions of the "big players" on the market and also presents a vision of how to link the online world with stationary retail.

Christin Susann Bugrahan, Online Marketing Manager at LLOYD Shoes

ProCampaign proves again that a privacy-compliant use of CRM systems is possible

Sebastian Meissner, Head of the EuroPriSe Certification

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