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Why web performance and responsive web design matter

The following post was adapted from Wicked Fast Websites, my free beginner’s guide to building fast websites and web apps that work on any device. Download it here.

A few year’s ago, Google ran an interesting experiment. Based on analyst research, they increased the number of search results displayed on a single page from 10 to 30. This added about 500ms—that’s just half a second—of extra load time to the page.

The result? Search traffic, and subsequently ad revenues, decreased by 20-percent.

Amazon ran a similar experiment, and found that delays of as little as one-tenth of a second had a negative impact on revenue:

In A/B tests, we tried delaying the page in increments of 100 milliseconds and found that even very small delays would result in substantial and costly drops in revenue.
– Greg Linden

Sites are getting bigger #

In 2009, the average website was 320kb. By 2010, it had almost doubled to 600kb. At the beginning of 2013, that number had tripled to 1.2mb. At the time of writing, the average website had ballooned to over 2mb in size. That’s six times larger than in 2009!

For a while, this exponential growth wasn’t a problem. We took for granted that both computers and bandwidth got faster and more reliable every year. And then mobile happened.

Mobile WTF! #

People are accessing the web from devices with varying levels of computing power and bandwidth. Desktops and laptops, phones and tablets, TVs, watches, video game consoles.

And for a growing number of people, mobile isn’t just one way they access the web—it’s the way they access the web.

A study by Google and Nielsen found that 77-percent of mobile searches happen at home or at work, locations where you would expect someone to have access to a PC. I’m sure you’ve experienced this before. You’re laying on the couch, you just got comfortable, and you realize you need to look something up. Rather than getting up and walking to whatever room you keep your laptop in, you just pull out the computer you always have with you—your phone—and Google it.

Harvard Business Review reported that 55-percent of Americans accessed the internet via a mobile device in 2012. The only surprising thing about that number is how low it is. But that same report also found that almost a third of all Americans used a mobile device as the primary way they access the internet.

Mobile isn’t just one way people access the web. For a growing number, it’s the only way.

Greater Performance Expectations #

Amazingly, despite the varied power and bandwidth of mobile devices, users expect them to be faster than desktops. Forty-percent of visitors abandon a website that takes more than 3-seconds to load

I’ve heard people argue that it doesn’t matter. 4G LTE, they say, is as fast as broadband wifi. And they’re right. LTE is awesome!

Until I go into Target or Home Depot. Or I hit that patch of trees down the street from my house, where I can’t even pull an EDGE network. Or when there’s a bad storm, and I still get internet, but it’s not LTE. And that’s here in the United States where we have a fantastic mobile infrastructure.

In developing nations, things are far less predictable, and that’s where mobile growth is really soaring.

Mobile is overtaking desktop traffic #

In the summer of 2012, India had an important milestone: mobile traffic overtook desktop traffic. China passed a similar milestone at the end of 2012. And in Korea, mobile search queries overtook desktop search queries.

Mobile traffic is surpassing desktop traffic, and not just in developing nations.

PAWS New England is a client of mine. They’re an all-breed dog rescue based out of-you guessed it-New England.

In May of 2011, mobile traffic accounted for just 9 percent of their overall traffic. That year, they switched from a desktop-only site to responsive web design. Twelve months later, mobile traffic was almost a quarter of all traffic to the site. And in March of 2014, mobile traffic surpassed desktop traffic, accounting for 52-percent of all traffic to the site.

While much of it comes from iOS devices, they had one visitor from a Nintendo DS, several from a Nintendo Wii, and an assortment of other (mostly Android-powered) smartphones and tablets.

The Perfect Storm #

There’s a myth about mobile users—that they’re always on-the-go and distracted, fleeting consumers of content.

But PAWS found that people aren’t just looking at dogs. They’re submitting (lengthy) application forms and making donations, too. Losing visitors to poor performance means fewer dogs saved and less money to fund their work.

We’re in the middle of a perfect storm. Websites are larger, devices are more varied and less predictable, and performance expectations are higher than ever.

Mobile-friendly, fast websites make more money #

Fast, responsive websites have a direct impact on your organization’s bottom line.

Have any questions or comments about this post? Email me at or contact me on Twitter at @ChrisFerdinandi.