Website Milliseconds Matter – But Why?

The evidence is conclusive; website page load time matters. The faster your website the more revenue your website will generate. Amazon and Google have studied this phenomenon. We have studied it and recently produced a great summary of their findings.'s findings re pages viewed per session versus page load speed

We all conclude that a faster website means very good things;

  • Reduced bounce rates
  • Increased number of pages per session
  • Increase number of check outs
  • Increased size of checkouts
  • Higher levels of customer satisfaction
  • Increased likelihood of customer returning

But Why?

Half a second of page load time seems inconsequential. When you view a page loading in isolation it is actually hard to feel or see that extra 500ms. But evidence shows conclusively that even 500ms matters on page load time. But, why does it matter?

Here is my Segue to an Answer;

A week or so ago I was climbing up a rock wall here in Boulder Colorado. Most of the time, I was focussed only on the wall and the moves I was making. But at times, I slowed down, lost rhythm and maybe started chatting with the folks on the ground. The climbing experience was the best and most fluid when immersed in the task at hand.

Chatting with a climbing partner after the session we started discussing this sensation and its applicability in other sporting scenarios; bombing down a hill through the trees on a mountain bike, hitting smooth and rhythmic turns through the bumps on skis.

We agreed that the immersive and fluid sensation of being buried in these (or any) activities, was consuming and truly special.


This sensation is one which has been referred to in a number of different ways by life coaches, psychologists, and various writers but for the purposes of today, lets refer to it using Mihály Csíkszentmihályi’s term; “Flow”

“the mental state of operation in which a person performing an activity is fully immersed in a feeling of energized focus, full involvement, and enjoyment in the process of the activity”

The state of flow is not just restricted to sporting endeavours. It can be achieved when pursuing musical interests, programming, gaming, learning etc.

Csikszentmihályi’s proposes that the human mind can process “110 bits of information per second”. When in a state of flow, a person’s mind will be wholly focussed on the task at hand. That 100bits of information per second will be wholly consumed by and within the task at hand.

Whilst performing one activity in state of flow, if we give the human mind an opportunity to receive and process information from an external activity then we give that mind an opportunity to become distracted and move out of a flow state.

Websites and Flow State

So perhaps, users of your website are more likely to stay on your website, learning about your product range, your pricing (or whatever it is that interests them) if they are not presented with an opportunity, be it ever so small, to receive and process information from some external source.

Clicking a hyperlink to load a web page is a natural opportunity for a break point in the flow state of a user on your website. The extent to which that break point impacts their flow state will depend on how quickly that next page loads.

Being in a flow state is a desirable state of being. When we reach it we associate the task at hand with a pleasurable experience.

I believe the longer a website can keep a user in a flow state on that website, the more pleasurable the user will believe that website is to spend time on; both during that session as a repeat visitor. Flow state users on your website will be not only good news for immediate revenue but also for brand association and longer term revenue.

While a 500ms improvement in page speed may not be noticeable for most users to the naked eye in a one off page load event, such a reduction reduces the period where your user has the opportunity to soak up information (55 bits in fact) from some source other than your website.

Regardless of the speed of your website, you should be pursuing performance improvement as a feature. It is a UX must have, not an option if you want to increase the chance for your users to view more pages, transact on your website and return for repeat visits.

Blog Categories

Interested in articles about a specific topic? Click on a category to see all related content. Sign up

Want to get started improving your website performance, scalability, and security? Sign up for a 14 day free trial of and see what we can do for you!

Get started