Context matters

Using eye-tracking to test email marketing

What makes a marketing e-mail or newsletter efficient? One can judge, for instance, by the number of users that opened the message or clicked on a specified element representing primary action, such as a product link or button.

Those indicators measure user engagement precisely; however, they are limited to the last phase of interaction with e-mail or newsletter. The act of clicking certain element in a marketing e-mail is a result of a longer process of identifying, assimilating, and analyzing its content. It is in those three steps that the decision is made to take action or not, and it is those three steps that are not analyzed or included in standard efficiency measurement, such as CTR or open-rate.

Therefore, click-through-rate or open-rate measures only completed processes, not taking into account those interrupted. Moreover, those parameters do not inform us about “why” a certain user decided to click or abandon the message.


One way to understand what is happening in users’ minds is to observe what they really see, which cannot be done using the traditional methods of e-mail research. Instead, we used eye tracking on a desktop computer to record the person’s gaze while looking at the e-mail message, checking which objects they looked at, for how long, and which elements, among the whole field of the vision, attracted their attention the most.

To check what kind of impact some of the characteristics of e-mails have on users, some of the stimuli were transformed by our team. For instance, we modified location of logo and the calls-to-action, changed size of prices, or flopped photos change the direction the person in the photo is facing.

Each of the stimuli used in the study had two versions–an original and a modified one. Each version was seen by 27 participants. All of the heat maps in the report are derived from the averaging of 10 second long scan paths of 27 subjects.

Observations: Testing known principles and their variations

Our different observations confirm some of the generally known design principles, such as users’ deep-rooted dislike of homogenous blocks of text.

At the same time, some of our hypotheses were disproved. For instance, reducing the length of introductory text did not result in an increased number of users reading it. In fact, introductory text was so rarely read that a general recommendation from our research is to remove it all together in favor of items that really matter.

Text and reading

Learning how to read and gaining experience in this activity shapes our perception since early childhood. In our (Western) culture, we read from left to right and from top to bottom. This becomes a strong habit and this strategy of scanning a visual stimulus is executed automatically, even if the viewed stimulus does not contain text.1

What is more, readers on the web are very selective.2 They constantly search for valuable content, but when the required amount of effort increases, their motivation plummets. Below, we describe further and illustrate those phenomena with the examples from our study.

Blocks of text

It may sound like a truism, but it is always good to have in mind that a homogenous block of text is not a good way to communicate with the Internet users.2 One can often observe in eyetracking studies that users tend to skip this kind of content, without making even the slightest attempt to read it.

Fortunately, there are some tips and tricks which can make the text more attractive to the user’s eye. First, formatting which includes clearly distinguishable headlines and leads often results in a phenomenon called F-pattern.

Fig. 1: A heat map showing an F-pattern


Readers have a strong tendency to scan headlines briefly, and they usually start to read from the top of the page. Their motivation to focus their attention on a written content decreases gradually, so you may expect that the first few headlines (counting from the top) will be read, and that the lower the headline is located, the less attention it will get.

Introduction text in an e-mail message

Reading requires time and effort, and the recipients of a newsletter want to quickly get exactly the information they are interested in (which usually means the special offers). It did not surprise us that introductory text in a newsletter would be ignored most of the time.3

But what to include in the marketing message instead of introductory blah-blah text? The answer seems obvious–more valuable content, such as the products we want to present.

Our study confirmed that hypothesis: After cutting most of the introductory text out, the amount of attention focused on it did not change much. On the other hand, the products presented in the message benefited greatly in terms of attracting users’ gaze.

Fig. 2: Scan paths. Left, without introductory text. Right, with introductory text.


Properties of numbers

The next thing we wanted to focus on was if numbers caught a human’s eye. Nielsen4 suggested that numbers written as numerals are eye-catching, whereas numbers written with letters are not, because they are indistinguishable from an ordinary piece of text.

Fig. 3: Heat maps. Left, the original version with large numbers. Right, the modified version, with downsized prices.


We studied how long the participants focused their gaze on numbers, depending on their size. The difference between small and large digits turned out to be statistically significant. The average difference between small and large number approximated 200 and 400 ms for both prices depicted in the stimulus. From the psychophysiological perspective, this is a long time. The longer we fixate on an object, the deeper the processing and understanding of the visual information.5

Communication through images

Pictures: What’s worth it, and what’s not

One of the widely known phenomena which can be observed in eyetracking and usability studies is so-called banner blindness. In short, web users tend to act as if they were blind to advertisements or other types of redundant information, which can only distract them from completing the task. This adaptive mechanism applies as well to stock photos and to pictures which do not present the real products or people. Pictures without informational value may even pull the viewers’ attention away from the valuable content because they may be easily classified as an advertisement, which is usually neither informative nor relevant.

Directing users’ attention by faces

Some types of pictorial stimuli are almost always classified as important. One of them is certainly a human face. We are social animals, so we are perfectly wired to automatically read the subtle social cues, for example those connected with decoding where the attention of another human being is directed at the moment.

Fig. 4: Scan path

Fig. 4: Scan path

And example of how this reflexive mechanism works can bee seen on the picture above. The participant automatically followed the gaze of the model right after noticing her face.

In the original version of this newsletter the model looked straight forward. We have created the modified version in which the model is looking at the logo. We tested both versions with our participants, and then we examined whether there is a significant difference in the amount of time the participants fixated on the logo. In the modified version, the average time of focused gaze on the logo was significantly longer.

Fig. 5: Heat maps. Left, the original version. Right, the modified version, with gaze direction diverted



Our observations and recommendations are rooted in a number of studies focused on what recipients do really see while looking at advertisements in email campaigns. Some of the effects repeated in our 2011 and 2013 studies; some of them were also confirmed in studies on the perception of the e-mails and newsletters carried out by other teams.

But we should not forget that those are general laws, which, however, in particular creation may be not fulfilled due to various mitigating factors, such as the content of the e-mail, its size, and the level of the audience engagement.


1Ziming Liu, (2005) “Reading behavior in the digital environment: Changes in reading behavior over the past ten years”, Journal of Documentation, Vol. 61 Iss: 6, pp.700 – 712

2 Nielsen, J., (1997), How Users Read on the Web, Retrieved 15 June, 2013, from

3 Nielsen, J., (2007), Blah-Blah Text: Keep, Cut or Kill? Retrieved 15 June, 2013,rom Ros Hodgekiss, (2011),

Email usability: The science of keeping it short and sweet, Retrieved 15 June, 2013, from­-sweet/ ]

4 Nielsen, J., (2007), Show Numbers as Numerals When Writing for Online Readers, Retrieved 15 June, 2013, from

5 Poole, A., and Ball, L. J. Eye tracking in human-computer interaction and usability research., Encyclopedia of human computer interaction. Idea Group, Pennsylvania, 2005, 211-219.

Posted in Discovery, Research, and Testing, Methods, Process and Methods, Usercentric | 1 Comment »

1 Comment

  • hermesbirkin311

    December 16, 2013 at 7:08 am

    wow, fantastic. Thanks for sharing

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