Why First Impressions Online Matter & How To Test Them

5 min readNov 3, 2016


In this article we’ll be focusing on the power of first impressions online, exploring how long it takes users to form their first impressions, the impact of the Halo effect and how you can test users first impressions.

Don’t Judge a Book by its Cover

We’ve all heard the old saying… ‘Don’t judge a book by its cover’.

It’s an old favourite, used to remind us that despite our best efforts to control it, we are pre-programmed to judge things based on our first impressions.

The saying therefore, acts as a reminder to encourage us to look past what first meets the eye and refrain from passing judgement until we’ve explored what’s beyond the surface.

My Copy of ‘Thinking Fast and Slow’ from Daniel Kahneman — Don’t Judge Me.

First Impressions and the ‘Halo Effect’

Imagine the following: Two candidates turn up for an interview. Candidate ‘A’ is standing, smartly dressed and well presented. Candidate ‘B’ meanwhile is slouching on a sofa, wearing an un-ironed shirt and ripped jeans.

Taking one look at the candidates, you’ll automatically make an assumption (which you may have just done by visualising these characters) that Candidate A is much more likely to impress in the interview.

Furthermore, you may also find yourself more likely to be more receptive and fond of candidate ‘A’ based on this first impression alone. This is a psychological phenomenon known as the ‘halo effect’ (where first impressions lead to biases in our later behaviour).

In the video below well know magician and mentalist Darren Brown showcases the impact the Halo Effect can have in the context of attraction.

First Impressions Online

So does this concept apply online? And if so how can we use it to inform our design decisions?

A recent study undertaken by the Missouri University of Science and Technology revealed it takes just 50 milliseconds for users to form their first impressions of your site. That’s just 0.05 seconds to leave an impression, and much like the previously explored ‘Halo Effect’ this first impression is large determining factor in whether the user chooses to stay and explore a website or leave to browse other sites.

“It takes just 50 milliseconds for users to form their first impressions of your site. That’s just 0.05 seconds to leave an impression”

Now, you may be finding it hard to believe that first impressions can form within just 50 milliseconds (and I wouldn’t blame you as I was too). However Google have also confirmed this 50ms in their own research carried out in 2012 which went on to further reveal that Design Opinions can even start to develop within just 17 milliseconds.

“Google reveal users can form design opinions online within just 17 milliseconds”

The report concludes that:

“We form first impressions of the people and things we encounter in our daily lives in an extraordinarily short timeframe. We know the first impression a website’s design creates is crucial in capturing users’ interest. In less than 50 milliseconds, users build an initial “gut feeling” that helps them decide whether they’ll stay or leave. This first impression depends on many factors: structure, colours, spacing, symmetry, amount of text, fonts, and more.”

You can read more on the research carried out by Googles Users Experience Research team here — ‘The role of visual complexity and prototypicality regarding first impression of websites: Working towards understanding aesthetic judgments’ (Snappy title eh?)

Users develop their first impressions of your site in under 0.05 seconds

The ‘Five Second Test’

The ‘five-second test’ first pioneered by Christine Perfetti at User Interface Engineering allows us to step into the minds of our users and provides us with insights on users first impressions, thoughts and feelings.

Christine Perfetti - The Five Second Test

To run a five-second test, simply gather up some participants, show them your homepage and set a countdown timer to sound an alarm in 5 seconds time.

Once the alarm sounds, remove the visual of the homepage and question the participants on their experience.

Typical questions to ask here would be:

  • What products/services does this business offer?
  • How does this sit make you feel?
  • Would you trust this site?
  • What was the first element of the homepage that caught your eye? etc.

Running a Five Second Test online

Struggling to find the right participants to take part in your test? No problem, nowadays, you don’t even need to perform this test in person, sites such as Five Second Test and User Testing allow you to conduct your 5 second test remotely via the internet and even source participants for you based on your screening questions, saving you the hassle of finding participants who meet your desired demographic.

5 second test from 5 Second Test.com


Users can form first impressions of your website in just 50 milliseconds, some design impressions can form in as little as 17 milliseconds. These first impressions can prove a vital indicator as to whether or not a user stays to explore your site or leaves (bounces). It’s therefore vital you test users first impressions of your site, this can be done by employing the 5 Second Test.

Originally published on my UX Blog www.kyecass.com

Found this article useful? Please feel free to leave a 💬 or quick ❤️ to let me know your thoughts. If you want to start up a conversation send a little 🐦 to @kyecass ✌️




Head of User Experience Design & Insights @Dept. Known for http://www.responsiveaxure.com and telling dad jokes. #UX & #analytics ninja.