Web pages bloat 25 per cent in a year

Pingdom report suggests images and scripting to blame

According to a report by Pingdom, web pages have grown at an astonishing rate over the past 12 months. The website monitoring company examined data from the HTTP Archive, looking at assets related to the top 1,000 sites in November this year and last. It found that over the past year the average size of a web page grew from 626 to 784kB.

Drilling down into the report, it appears every major type of content has grown, but there are two main culprits: images and scripts. While the jump in image sizes isn't massive from a percentage standpoint (21.2, according to the report, which is less than the leap in CSS), the previous average means that the overall size has risen sharply, from 372 to 451 kB. JavaScript saw the fastest growth, though, up almost 50 per cent, from 103 to 149 kB.

According to Pingdom, the dramatic rise in JavaScript is "most likely tied to the rise of HTML5, with websites using JavaScript as an increasingly important part of a dynamic web experience". However, as the report notes, the rapid growth in mobile browsing means that developers should take care to optimise their sites, rather than making the assumption those visiting are on increasingly powerful machines tied to fast connections.

"Web pages have been growing in size all along. The Web experience is constantly getting richer, getting more content, and people in general are getting increasingly capable Internet connections. It's a natural progression," concludes the report. "That doesn't mean we should stop caring about page size, though. It's still an important speed factor, and with today's freely available developer tools there are so many easy ways to analyze and optimize web pages that there really are no excuses for overly bloated websites."