Email Marketing KPIs That Matter

Email marketing metrics provide essential insights into how your campaigns are performing.

List Growth Rate

A healthy list growth rate indicates that your content is valuable enough to attract new subscribers while retaining existing ones. This metric is crucial for building a solid email list over time.

List Growth Rate = Total Subscribers at Start of Period- New Subscribers + Unsubscribes​×100

You gained 100 new subscribers this month, lost 20, and started with 2,000.
List Growth Rate = ((100 – 20)/2000) × 100 = 4%
***A positive growth rate means your list is expanding and healthy.***

Revenue per Email (RPE)

For e-commerce businesses, the revenue per email (RPE) metric helps you understand how much revenue each email generates. This is a direct measure of the financial impact of your email marketing efforts

RPE=Emails Delivered /Total Revenue​

Your campaign earns $500 in sales from 1,000 emails sent.
RPE = $500/1000 = $0.50 per email
*** A solid metric for calculating ROI, especially in eCommerce***

Forward/Share Rate

The forward/share rate measures how often your recipients share your email with others, indicating that your content is valuable enough to be passed along and potentially reach a wider audience.

Forward Rate = Emails Delivered/Forwards​×100

Out of 1,000 recipients, 15 people forwarded your email or shared it via social.
Forward/Share Rate = (15/1000) × 100 = 1.5%
***This suggests your content was valuable enough for recipients to pass it on.***

Spam Complaint Rate

Tracking your spam complaint rate is essential for maintaining a positive sender reputation. A low spam complaint rate ensures your emails land in inboxes and not in spam folders, improving your deliverability.

Spam Complaint Rate=Emails DeliveredSpam Complaints​×100

3 recipients marked your email as spam.
Spam Complaint Rate = (3/1000) × 100 = 0.3%
***Anything above 0.1% can hurt your sender reputation; this signals a need to review your list and content relevance***

Engagement Rate

The engagement rate measures the overall interaction with your emails, including opens, clicks, and shares. High engagement rates indicate that your content resonates well with your audience and keeps them interested.

Engagement Rate = Emails Delivered Interactions (Opens, Clicks, Shares)​×100

Out of 1,000 emails sent, 300 were opened, 70 were clicked, and 10 shared.
Engagement Rate = (300 + 70 + 10)/1000 = 38%
***This indicates how actively people are interacting with your emails overall***

Open Rate

The open rate measures how successful your email subject lines and send times are in capturing the attention of your audience. A higher open rate means your subject lines are engaging and resonate with your recipients.

Open Rate=Emails DeliveredEmails Opened​×100

You send an email titled “Don’t miss 50% off this weekend only!” to 1,000 subscribers.
Out of those, 350 people open the email.
Open Rate = 35%
***This tells you your subject line was attention-grabbing and well-timed***

Click-Through Rate (CTR)

A strong click-through rate (CTR) shows that your email content is compelling and drives recipients to take action, whether it’s clicking a product link, signing up for an event, or downloading a resource.

CTR=Emails DeliveredTotal Clicks​×100

In the same email, you include a button that says “Shop the Sale.”
Out of the 350 who opened it, 70 people click the button.
CTR = (70/1000) × 100 = 7%
***This shows how engaging your content and CTA were to the full list.***

Bounce Rate

The bounce rate helps you assess the quality of your email list. A high bounce rate may indicate that you’re sending emails to invalid or outdated addresses, negatively impacting your email deliverability.

Bounce Rate=Emails SentBounced Emails​×100

You send the email to 1,000 people, but 40 of the addresses are invalid.
Bounce Rate = (40/1000) × 100 = 4%
This indicates issues with your list quality and a need for cleanup.

Unsubscribe Rate

Monitoring the unsubscribe rate is crucial for understanding how your audience perceives your emails. If too many people unsubscribe, it may be a sign that your content is irrelevant or your email frequency needs adjustment.

Unsubscribe Rate=Emails DeliveredUnsubscribes​×100

Out of the 1,000 recipients, 12 people unsubscribe.
Unsubscribe Rate = (12/1000) × 100 = 1.2%
*** A slightly high rate like this may mean the content isn’t resonating or you’re emailing too often.

Conversion Rate

The conversion rate is one of the most important email marketing metrics, as it shows how many recipients complete the desired action (such as making a purchase or signing up for a service) after clicking on a link within your email.

Conversion Rate=Emails DeliveredConversions​×100

Of the 70 people who clicked the sale link, 10 made a purchase.
Conversion Rate = (10/70) × 100 = 14.3%
***This shows how well your email content and landing page converted interest into action***

By regularly monitoring these key email marketing metrics, you can optimise your campaigns for better results, increase engagement, and improve your return on investment (ROI). Understanding these metrics empowers you to make data-driven decisions and create more personalised, effective email marketing strategies.