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Maura Monaghan
Maura Monaghan

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Website Speed Statistics: What Are the Effects of Slow Load Time?

We all know first-hand that slow websites aren’t ideal. Slow loading times do real damage to a site’s bounce rate and SEO, and every second counts – check out the average increase in bounce rate per second for proof:

bounce rate timeline

Website load time is important for everyone, but it’s particularly important for ecommerce websites, for which time is quite literally money. Below, I’ll explain just how dramatically site speed can affect sales and customer loyalty – and offer some tips for easy improvements! But first, let’s talk about a big differentiator in website load times: mobile vs desktop browsing.

Website Speed on Mobile vs Desktop Devices

Websites load faster on desktops than on mobile devices – a lot faster, in fact. One study of 5 million desktop and mobile pages even found that the average time it takes to fully load a webpage on desktop is more than twice as fast as on mobile!

That said, the convenience of mobile browsing has still managed to keep it on top. One 2018 study of US web traffic revealed that mobile devices account for nearly three fifths of site visits and nearly half of total time spent online. Check out this breakdown:

mobile vs desktop speed

Mobile browsing is hugely popular, and mobile users tend to have high standards, too: most mobile users expect pages to load as fast or faster than they do on desktop. One study of consumers in the UK even found that 14% of shoppers expect pages to load instantly on mobile.

But don’t worry about meeting impossible expectations! There are plenty of realistic goals to set instead: more than half of smartphone users expect pages to load in under four seconds, which is a very doable goal!

What Industries Are the Most Mobile?

55% of all time spent on retail websites takes place on a mobile device, and it makes sense for every type of website to perform on mobile. But some industries are even more mobile-focused than others:

mobile visits by industry

That said, the desktop user experience is not to be underestimated. For all 17 industries above, bounce rates were lower on desktop than on mobile:

bounce rate by industry

Every industry also had a longer average time on site for desktop over mobile, except for Books and Literature – an outlier that I’d guess can be explained by mobile reading devices.

How Does Site Speed Affect Sales?

A one second page load time makes users feel stress-free and in-control. But after 10 seconds, their attention is barely kept, and they are unlikely to visit the webpage again. For ecommerce sites, the cost of page delays will show in revenue. If you’re running an ecommerce site that makes $100,000 per day, then a one second page delay could cost you twenty-five times that amount annually in lost sales!

Even if your site isn’t making that kind of money, a one second delay will…

  • Reduce page views by 11%
  • Decrease customer satisfaction by 16%
  • Reduce conversions by 7%

The good news is, you can experience massive uplifts even from the slightest improvement in load time. In fact, increasing site speed by even 0.1 seconds can have a positive impact on sales:

site speed improvement

How Does Site Speed Affect Customer Loyalty?

Customer loyalty is just as important as conversions, since most dissatisfied customers will choose a different site the next time they shop! And just as speed impacts conversions, it also has dramatic effects on customer loyalty. Check out these fast facts:

Customer engagement also suffers as a result of slow load times. Users spend more time on a website when its pages load faster – on average, users visit 8.9 pages when load time is two seconds, versus just 3.3 pages when load time is 8 seconds.

All websites have to deal with the consequences of load speed, not just small or DIY sites – even the BBC loses an additional 10% of users for every extra second it takes for its site to load.

How Can Site Speed Be Improved?

Simple improvements to site speed can make a world of difference, and there are plenty of easy fixes to implement. The best way to begin is to identify the simplest factors affecting load speed:

  • Web hosting: It’s important to choose a hosting provider wisely, since a low uptime guarantee or subpar customer support will keep your site from running smoothly down the line. It’s also important to note that the more files your website uses, the more server space it will need – which means you may have to upgrade from shared to VPS or dedicated hosting as your site grows.
  • Images, videos, and files: The larger your files are, and the more files you have on a page, the longer it will take for the page to load – which means it’s important to optimize your images as much as you can before uploading them.
  • Plugins: WordPress plugins are great for adding advanced functionality to a website. However, it pays to be selective about the number of plugins you use, because too many at once will overwhelm your server.
  • Browsers: Older versions of browsers may be incompatible with newer assets and code on your pages, so it helps to ensure you’re using the most recent version of your chosen browser.

Once you’ve identified the factors you want to work on, it’s time to start making some improvements, such as:

  • Optimize images: Optimizing images is a balancing act of finding the lowest file size with the most acceptable quality. There are countless free tools available that make this task a super simple way to reduce a webpage’s weight.
  • Optimize code: Minifying your code can massively improve page speed. There are many different tools that can help you do this, like HTMLMinifier for HTML or UglifyJS for JavaScript.
  • Optimize databases: Clearing your database of unnecessary items will make it smaller, and make it easier for web hosting servers to fetch requested content quickly. Think of it as a spring cleaning of unapproved comments, post drafts, and trashed pages!
  • Use a CDN: Content delivery networks distribute bandwidth across multiple, geographically diverse servers, rather than leaving one server to handle all of your traffic. Cloudflare is one popular CDN option, although there are many more available.

Website Load Time: Final Thoughts

Fast load time should be a major goal for any website owner trying to improve bounce rates and engagement. Ecommerce site owners in particular will notice the financial benefits of upping their site speed.

The best news is that there are simple fixes we can all implement quickly to improve our site speeds – but keep in mind that no matter how much you optimize a site, the desktop browsing experience will still differ from the mobile one!

Top comments (1)

simus51 profile image

Great article Maura! I've been trying to convince one client the importance of site speed and to allocate time on this task. Some of these stats should help.