The growing epidemic of page bloat

The average web page is now more than 1 megabyte (MB). This isn’t a case where bigger is better, it’s bad for site owners and for mobile users.

Back in December, I predicted that at some point in 2012 the average web page would surpass 1 MB in size. That point has arrived — a little earlier than even I expected. On May 1, the newest web page stats released by the HTTP Archive revealed that the average web page is now a whopping 1042 kilobytes (1024 kilobytes equals a megabyte).

What’s behind rampant page bloat?

To put things in perspective: at the time I made my prediction, the average page was 965 KB. That’s 8 percent growth in just four months. Doesn’t sound like much? Then consider this: Back when the HTTP Archive started tracking page stats in November 2010, a mere 18 months ago, the average page was an already hefty 702 KB. Pages today are almost 50 percent bigger than that.

If pages continue to grow at this rate, the average page will hit 2 MB by 2015.

The main culprits for this growth are images (which account for more than half of the average page size) and third-party scripts like analytics, ads, and social sharing buttons. But what’s really behind it is our insatiable desire for richer, more dynamic content — coupled with site owners’ desire to track user behavior and get us to share their content using every conceivable widget.

Mobile users are the biggest losers.

While bigger pages hurt performance for desktop users, too, the biggest victims of page bloat are mobile users. Not only does a 1 MB page take forever to load, it can also deliver a nasty case of sticker shock when you get your phone bill. To give you a for-instance, earlier this month I was traveling in Europe. Before I left home, I bought 25 MB of data from my provider for $ 100. In other words, I’m paying $ 4 per page.

And if your service provider doesn’t hit you with a huge bill, they’ll hit you with a data cap and throttle your service. A 2 GB data plan sounds like a lot, but if you watch videos, listen to music, and download ebooks, it doesn’t get you very far. (Consider that 1 MB equals about 20 seconds of medium-quality video or 45 seconds of music.) The proliferation of 1 MB pages will catapult you to your data cap that much sooner.

But this doesn’t only cost mobile users. Bloated pages cost site owners too. Bigger pages inevitably take longer to load. There’s a huge body of research that shows that when people visit slow sites, they spend less, view fewer pages, click fewer ads, and spend less time on site. This applies both to mega-sites like Amazon (which famously announced that for every 100 milliseconds of slowdown, they experienced a 1 percent drop in revenue) and smaller “mortal” e-commerce sites like auto parts vendor AutoAnything (which found that by cutting page load time in half, it grew revenue by 13 percent).

How much bigger can pages get?

Like it or not, this kind of growth is the norm, and it’s going to continue to be a problem for users. Sure, today’s devices, browsers, and networks are incredibly powerful compared to the clunkers of 15 years ago, but here’s the problem with our great big juicy hominid brains: you can pretty much count on the fact that if you have a team of technology geniuses in room A working to fix one problem, there will be a team of equally brilliant people in room B developing a technology that will create a new problem.

So while devices, browsers, etc. are always getting better, we’re also developing more and more bandwidth-hogging content. At best, the two factions are neck and neck. Where this will take us is anyone’s guess.

Joshua Bixby is president of Strangeloop Networks, a company that provides website acceleration. Bixby also maintains the blog Web Performance Today. He can be found @joshuabixby on Twitter.

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