Would improved site speed increase conversion?
(and make you more money?)
Spontaneously we would say yes without even thinking about it. But we want evidence and need some numbers here, so we looked at some great case studies.
Google ran some interesting tests showing that a slowdown of just 100 to 400 milliseconds have an measurable impact of -0.2% to -0.6% on the number of searches per user.
AOL presented statistics that clearly showed page views drop off as page load time increased; users with the fastest page load time viewed on an average 7.5 pages per visit, users with an average page load time viewed 6 pages/visit and users whose page load times were slower than average viewed 5 or less pages/visit.
The most impressive statistics about the impact of site speed came from ShopZilla. They increased their site speed by 5 seconds (from 7 to 2 seconds) and the result was a 25% increase in page views and 7-12% increase in revenue!
This clearly indicates that visitors feel more secure and have more trust in a fast interface. They stay longer on the website and look at more pages which results in more conversions.
Would a faster website be a better experience for visitors?
Seeing the results above we can also answer this question, with YES.
We all know what we do when we get annoyed with a slow loading website. We either close it down or start pressing every single button on the site hoping that it does something. Especially on e-commerce websites where visitors enter personal information, slowdowns are very untrustworthy and do not encourage the visitor to finish a checkout process or come back.
Would an improved site speed improve rankings?
Google already publicly announced that they are using a website's loading time as additional ranking factor. At the time Google made this announcement just 1% of search queries were affected by the site speed signal for visitors searching in English on Google.com. This is likely to have increased by now and it looks like site speed will be a bigger factor in determining your rankings indirectly. Just recently Google Analytics annouced the new functionality of tracking page speed.
In other words improving your website's loading time, improves your websites quality - visitors feel more secure and stay longer and they visit more pages which increases your click through rate and conversions. All these factors combined will have a positive effect on your website's rankings.