Lately in some of my writing projects I’ve had to hunt down sources to demonstrate the importance of web page speed. Usually a quick Google search will pull up some pretty good ones, and I have a few others on file that I can refer to.
I thought I would put together a roundup of some of the ones I’ve been able to find. Web development bloggers, who are constantly promoting the importance of web page speed, should have these types of authoritative sources at their fingertips.
So consider this post the collective evidence for the importance of page speed. Posts are listed from oldest to newest.
- Google’s Marissa Mayer: Speed wins
Dan Farber, ZDNet (November 9, 2006) - Page Load Times vs Conversion Rates
Gabriel Svennerberg, In usability we trust (December 18, 2008) - Amazon: 1% Revenue Increase for Every 100ms of Improvement
Strangeloop (2009; from archive.org, original broken) - Speed Matters
Jake Brutlag, Google Research Blog (June 23, 2009) - Bing and Google Agree: Slow Pages Lose Users
Brady Forrest, O’Reilly Radar (June 23, 2009) - Velocity and the Bottom Line
Steve Souders, O’Reilly Radar (July 1, 2009) - More on how web performance impacts revenue…
Jesse Robbins, O’Reilly Radar (October 1, 2009) - Business impact of high performance
Steve Souders, stevesouders.com (October 6, 2009) - The Performance Business Case
Stoyan Stefanov, Book of Speed (2011) - Speed Is A Killer – Why Decreasing Page Load Time Can Drastically Increase Conversions
Sherice Jacob, KISSmetrics (May 10, 2011) - Page load time – the online business killer
David Mercer, Business Insider (May 24, 2011) - 4 awesome slides showing how page speed correlates to business metrics at Walmart.com
Joshua Bixby, Web Performance Today (Feb 28, 2012; from archive.org, original broken) - For Impatient Web Users, an Eye Blink Is Just Too Long to Wait
Steve Lohr, NYTimes.com (Feb. 29, 2012) - How One Second Could Cost Amazon $1.6 Billion in Sales
Kit Eaton, Fast Company (March 15, 2012) - Why Website Speed is Important
William Craig, WebFX (April 2, 2014; originally by Smriti Chawla, Six Revisions) - Site Speed is (Still) Impacting Your Conversion Rate
Jackie Jeffers, Portent (May 9, 2014; Updated August 20, 2019; originally by Ian Lurie) - Why Faster Websites Make More Money [Infographic]
WebpageFX Team (July 23, 2014) - Case study: Mobile pages that are 1 second faster experience up to 27% increase in conversion rate
SOASTA (September 1, 2015; archive.org, original broken) - WPO Stats
Everts/Kadlec - The need for mobile speed: How mobile latency impacts publisher revenue
Think With Google (September, 2016; Originally by Alex Shellhammer, DoubleClick) - How Page Load Time Affects Conversion Rates: 12 Case Studies
Zuzana Padychova, Hubspot (March 23, 2017) - How Website Performance Affects Conversions
Abralytics (April 19, 2022) - Page Loading Time: The Secret Sauce to High Conversion
Leeline Sourcing
If you know of any other good sources that discuss why page speed matters, add them to the comments and I’ll continually update this post. And keep in mind, these are sources that show why page speed matters not how to make pages faster.
So if you’re heading to a client meeting or want to discuss with your boss why it’s wrong to polyfill some CSS3 or HTML5 feature so it works in IE6/IE7/IE8, this might be a good way to show the potential effects of slowing down the slowest browser.
Thanks for this, really useful information.
Dig the roundup of articles. Before I finished the redesign/re-engineering of my site, I grabbed the PageSpeed addition to Firebug and heeded it’s warnings. After quite a few hours of optimizing the front-end scripting and server output, I managed to get PageSpeed scores of 90-95. http://focus97.com
Now we do the same for client sites. It’s tough to gauge the true ‘experience’ from a user/visitor’s perspective, but average visit times have increased, perhaps owing to the speed not being a distraction (i.e. when it was slower).
Thanks, these are really useful links and some helpful advice for shrinking load times. I know its important to cater for the slowest but I still feel like should design for the fastest – survival of the fittest! If you can’t keep up, get out the race… or update your browser or your hardware! Wrong, I know, but everyone is entitled to an opinion.
Thanks, very useful article :-) Good links, and a lot of information on shrink loading time. Unfortunatly, we do’nt have any good tip.
As a long time web application developer I’ve found that working on a fast application lets me work so much faster. The faster I can load up and get to a page, the faster I can make changes on it or fix bugs, etc. Maintaining a slow application just slows everything down, testing, development, etc.
Very applicable content! There are many times where I am very frustrated by slow sites. Many people are unwilling to spend the extra cash to ensure speed, but it is ultimately worth it when it comes to web design and general website formation!
thank you for this Article
Very good website !
A relevant list by Steve Souders:
Performance Tools
More relevant links:
http://blog.chriszacharias.com/page-weight-matters
http://www.bookofspeed.com/
https://developers.google.com/speed/
And more:
How Does Reducing JavaScript Requests & Minifying JavaScript Impact Site Performance?
Creating a Performance Culture
Two good slide decks on this topic:
http://www.slideshare.net/joshfraz/sept-2012rumtalk
http://www.igvita.com/slides/2013/breaking-1s-mobile-barrier.pdf
Relevant:
http://econsultancy.com/uk/blog/63185-14-brands-that-increased-conversion-rates-via-responsive-design
the faster your site – the higher it will be in search engine results – so… it always make sense to minify your js