This article has been updated with new data. It was originally published in February 2017.
Today, it’s critical that marketers design fast web experiences across all industry sectors. People want to quickly pay bills on finance sites, get rapid results when they’re browsing holiday reviews, and view an article immediately when they click through. And if there’s too much friction, they’ll abandon the site and move on.
Here’s the good news. Since we looked at mobile page speeds last year, the average time it takes to fully load a mobile landing page has dropped by seven seconds.1 The bad news is that it still takes about 15 seconds, according to our new analysis. That’s far too slow when you consider that 53% of mobile site visits leave a page that takes longer than three seconds to load.2
Our data shows that while more than half of overall web traffic comes from mobile,3 mobile conversion rates are lower than desktop.4 In short, speed equals revenue.
Last month, in an effort to get a better sense of how Google’s advertising partners are doing, we did an analysis of 11 million mobile ads’ landing pages spanning 213 countries.5 That analysis confirmed our thesis: Even as most traffic is now occurring on 4G instead of 3G,6 the majority of mobile sites are still slow and bloated with too many elements.
We dug deep into a wide range of sectors from finance to travel. Pages from the automotive, retail, and technology sectors, on average, take the longest to load. And they also have some of the most bloated pages on the web.
Our research has been eye-opening. For 70% of the mobile landing pages we analysed, it took more than five seconds for the visual content above the fold to display on the screen, and it took more than seven seconds to fully load all visual content above and below the fold.7
We also trained a deep neural network — a computer system modeled on the human brain and nervous system — with a large set of bounce and conversions data. The neural net, which had a 90% prediction accuracy, found that as page load time goes from one second to 10 seconds, the probability of a mobile site visitor bouncing increases 123%. Similarly, as the number of elements — text, titles, images — on a page goes from 400 to 6,000, the probability of conversion drops 95%.8
No matter what, faster is better and less is more.
And sometimes, leaner is better too. We found that 79% of pages were over 1MB, 53% over 2MB and 23% over 4MB.9 One image in particular caught our attention: It weighed a whopping 16MB.
But despite the bad news, there’s plenty of low-hanging fruit. Simply compressing images and text can be a game changer—25% of pages could save more than 250KB and 10% can save more than 1MB that way.10 Our analysis shows that the retail, travel, and healthcare sectors have the most room for improvement.
When it comes to mobile pages, speed and size matter. Marketers must keep people engaged on mobile and focus on building mobile-first experiences. Check out the charts below for a global perspective on mobile across industry sectors, including guidelines for speed, webpage size, and the number of content pieces per page.