The shocking reality of website response times
Every second counts when it comes to the load speed of a webpage. Longer webpage loading times can cost businesses serious amounts of money. A one second increase in website response time equals 11% fewer page views, a 16% decrease in customer satisfaction and a 7% loss in conversions. For example, a one second increase in Amazon’s page load would annually cost $1.6 billion in sales (Aberdeen Group). Walmart found that for every 1 second of performance improvement, it gained a conversion increase of up to 2%.
But despite the impact that speed has on conversion rates and customer satisfaction there is a very worrying and surprising trend: websites are getting slower! The average website is actually slower now than it was last year. This is a consistent trend that we’ve seen for the last few years.
Has webpage loading speed changed over time?
It made me wonder if the slowdown is a uniform trend across all sites, or if it only affects a subset of the web. So I took a closer look at the actual loading speed of webpages, and how it changes over time. I used data from the HTTP Archive which is a wonderful repository for big data analysis of anything relating to website performance and how the web is built. It stores the metrics from monthly crawls of about 500,000 of the Alexa Top 1,000,000 Sites.
I specifically looked at a metric called SpeedIndex which is a measurement of how quickly the screen paints (perceived load time). It’s expressed in milliseconds, so the faster you paint the whole screen, the lower the score.
In order to understand if the slowdown just affects websites with average performance or slow performance, I graphed the 10th, 25th, 50th (median), 75th and 90th percentiles (e.g. 10th percentile = the fastest 10% websites) and here are the depressing results:
Note: The lower percentiles are the faster sites, and the higher percentiles are the slower sites.
So, despite some anomalies that may be caused by the nature of synthetic monitoring, we can see an upward growth to all these lines for the last 2 years. This means that all sites across the Alexa top 500,000 websites are getting slower over time. For instance, the 10% fastest websites are on average getting 29ms slower each month, and the median sites are adding 67ms every month (assuming a linear trend).
What is causing webpages to slow down?
The main reason is simply page bloat. The average webpage size is now 2.1 MB, according to the HTTP Archive. That’s two times larger than the average site from three years ago.
Websites are adding more and bigger images, attention-grabbing videos, and other code and script-heavy features that are negatively impacting response times, especially on slower mobile connections. In addition, the use of tracking and analysis tools to learn more about visitors has grown significantly. Frank would need two of these floppy disks to store one page of an average website now:
What can I do to ensure my webpages load quickly?
While websites are getting slower, customer expectations are getting higher, with most consumers expecting pages to load in 3 seconds or less. Using effective performance monitoring, you can make sure you’re webpages are loading as quickly as your customers expect them to.
Borland Silk WebMeter monitors your website for availability and responsiveness every 15 minutes, and emails you with daily reports so you know exactly how your website is performing. If your website is down or takes too long to respond, Borland Silk WebMeter alerts you immediately, so you can get straight on it. You can simulate popular web browsers from your iPhone or Android mobiles, as well as from Internet Explorer, Firefox and Google Chrome.
For large scale website usage, Silk Performer CloudBurst provides unlimited scalability from the Cloud. Simulate peak-loads of any size from multiple places throughout the world, without even having to invest in load testing hardware and setup. With Silk Performer CloudBurst’s diagnostic tools, you can easily locate root causes of performance problems, even under peak loads, enabling you to get straight to the problem and fix it immediately.
Remember, every second counts when it comes to the load speed of a webpage, so make sure you closely monitor you website’s performance using some world class performance testing tools. Before it costs you serious money.
Try it for free now: Silk Performer WebMeter
Register now to explore Silk WebMeter’s performance testing capabilities, including daily reports, statistics and error notifications. It takes you just a few steps to get started.
Try it for free now: Silk Performer CloudBurst
Register now to run your free performance tests in the Cloud, with 200 complementary CloudBurst Credits.