Email click-through rates are one of the most valuable pieces of data when it comes to measuring the effectiveness of your email campaign.

While open rates tell you how many people are seeing your email in the inbox and deciding to open, your click-through rate tells you how many of those people are acting on the content you send out.

Depending on the goal of your email marketing, a high click-through rate could mean more people visiting your website, redeeming your offer, or registering for an upcoming event.

Recently, we set out to learn more about what type of content works best for generating high click-through results.

Specifically, we wanted to learn more about how the length of text and number of images in an email impacts click-through rates, and whether or not there is an optimal amount that you should be using.

To help us find out, we analyzed over 2.1 million Constant Contact customer emails. To ensure that the data was accurate, we only analyzed campaigns sent to more than 100 subscribers.

We found that — with some industry-specific exceptions — emails with three or fewer images and approximately 20 lines of text result in the highest click-through rates from email subscribers.

Here is a closer look at the numbers:

Click Rate Images IMG

Click Rate Text IMG

What does this mean for you?

In today’s increasingly mobile world,  consumers want to be able to read content anywhere, at any time, and from any device. These findings validate the fact that — in general — shorter more concise content performs better than longer, more convoluted email campaigns.

By keeping your emails straightforward and your content clear, you can craft emails knowing that your subscriber can read them with equal ease at their office desk, while waiting for the train, or at home.

Of course, it’s important to note that these findings represent what we’re seeing across a large spectrum of Constant Contact customers. It remains as important as ever to test to see what works among your own email subscriber base.

Next steps…

Take a look at your latest email campaigns — how do the amount of text and images compare to our overall results? Have you noticed any connection between the amount of text or images and your click-through rates?

We’d love to know what’s working for you and hear your ideas for improving click-through rates.

We’ll be digging deeper into this data over the next few weeks and uncovering some interesting industry trends, so stay tuned!