TL;DR (takeaways for the impatient)
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As we say in a number of places on geking.com, we believe small business owners do better by working on their businesses, rather than trying to become experts on web technology. We provide information like this page for those owners who need to understand a bit more before they are ready to improve their website and to hire a consultant to assist them. We are constantly updating our site and adding to the information about creating more productive websites. If you still have questions, please feel free to email us (webhelp at geking.com) or call us (817.500.4501 9-5 Central).
When a visitor clicks on a link or types a URL into a browser, the browser requests an address from the Domain Name System (DNS). The DNS converts the human-type URL (mydomain.com) into an Internet Protocol (IP) address (002.240.001.240). The browser then sends a request for the page to that address. The web server at that address finds the page (if it exists) and sends a response to the browser, and then downloads the elements that make up the web page, starting with the HTML. The browser interprets the HTML and begins to render (display) the page. The browser then requests each element, such as images, videos, style sheet files, script files, etc. according to the addresses in the HTML. When the browser has received all the elements and displayed the page on the visitor's screen, the web page is said to be 'fully rendered'.
Page speed is measured from the time a browser sends a request to the web server until the page is completely displayed (“fully rendered”) by the browser. The web server will send the HTML and text for the page to the browser, and the browser will begin to download and display other elements (images, videos, etc.) until all of the elements have been displayed.
How long a page takes to fully render results from a number of factors:
The size of files is obviously important to page speed as bigger files take longer to transit the Internet. The number of files is also important as each file seprately listed in the HTML must be requested by the browser. The location of files is important because files located off the web server, such as font files, CSS files, video files, etc., requre the browser to locate and send a request to a different server, thus starting the time to first byte delay over again for each different server.
Page speed is not a technical concern - it is a vital part of your website's success. Visitors expect faster and faster results from websites. In Akamai's 2015 study1, they found that 49% of consumers expect pages to load in 2 seconds or less. Their research also showed that website visitors' patience has fallen from 63% willing to wait for a website to load to 51% today. Even worse for slow websites, 30% of e-commerce consumers now (2014) expect page load times of 1 second or less. What does this mean for your website? It means a slow website will cost you far more than you will know. According to Akamai,
"50% of dissatisfied users will visit another website to accomplish their activity. More than 1 in 5 will leave for good — 22% won’t return to a website where problems have occurred. It doesn’t end there… after a poor experience, 45% are less likely to visit a website again, 35% will have a more negative perception of the company and 32% are less likely to make online transactions with the company."1
To underscore the importance of page speed to visitors, consider the results of the Neurons, Inc. study for Ericsson2 that reported, "A neuroscience study measuring user reactions to network performance has shown that delays in loading web pages and videos while completing tasks under time constraints are taxing – heart rate and stress levels increase. Both time-to-content and additional delays due to re-buffering lead to decreases in Net Promoter Scores (NPS). On the other hand, smooth browsing and video streaming lead to increased NPS for a mobile broadband service provider." Don't stress your visitors with slow speeds - they're your most precious web resource.
Both Google and Bing have stressed the importance of page loading speed as part of the visitor experience. Both Bing and Google also indicate that quick click-backs (someone returning immediately to the search engine results page) can be interpreted as a poor result for the visitor, and this can result in lower ranking for your page. Since visitors leave in increasing numbers as pages take more time to load, if your website does not meet visitors' expectations of 1 - 2 seconds to load, you not only lose current visitors, but your site may score more poorly on search results, giving you fewer visitors in the future.
While it may take an expert to accurately determine and fix what is slowing down your page speed, it is easy and free for you to see how long it takes each of your pages to load. Webpagetest.org provides a simple to use mechanism to see how long a page takes to load. If you point your browser at Webpagetest.org, you can enter the URL of any of your pages, choose a location to test from, a visitor connection speed and a browser. If your business serves a local area, choose a location close to your business, but if you are serving a national or international audience, test with different locations.
In less than a minute, the site will complete the test and provide you with a detailed look at how fast the page loaded, and how each element on the page was loaded. While the test is easy to start, understanding the results can take a bit of time and experience. Because we feel your time is best spent on your business and not in becoming a web expert, we suggest you stick to the high level portions of the test results, shown in figure 2.
Check the letter grades for your website; B's or better are OK
All of these except first byte time have to do with server settings for your website. Changing these may be beyond your expertise, or may not be adjusted for the type of hosting your website runs under. Your principal concern will be any grades below “B”. The good news is that most of these settings can be quickly and inexpensively changed by a competent web developer. If your website hosting provider tells you these settings cannot be changed, you may decide to move your website to another hosting provider that does allow users to adjust them. A web developer will require access to your hosting account to make any changes, and it is a good idea to change your password as soon as the work is complete.
First byte time is a measurement of the time between a browser request for a web page and the delivery of the first byte of the response by the web server. First byte time has two components, DNS lookup, and server response. DNS lookup is the time required for a browser to negotiate the Domain Name Service to find the Internet Protocol address of your website. Any delay beyond 500 milliseconds (1/2 second) means your server is slow in responding to the browser. First byte time is dead time as far as the visitor is concerned. While there are some steps that we can take to get a part of your web page displayed while other parts are still loading, nothing can work around a slow first byte time. Run the webpagetest several times and keep an average time to first byte. If the time required for the DNS or for time to first byte exceed 1/2 second, you should contact an optimization consultant (like us). You may receive the advice to move to a different hosting provider or to a more expensive (and faster) hosting package.
To see more of what is happening during the page load, you can click on the image below the subtitle "Waterfall", seen in figure 2a.
The "waterfall display" looks like a waterfall, running from the top left to the bottom right, with a separate line for the request for each element on the page. The display shows the time required for DNS response, first connection between the browser and the server (for that element), time to first byte from the server and the time required to download the element.
Typically, a waterfall display wider than it is tall shows a fast download, while a very tall waterfall shows a page load that requires a good deal of time, with many elements on the page. If your page contains many elements, or if one or more elements are taking a long time to download, you should consult with an optimization consultant who can work with your design to minimize the number of files and the accompanying delay. It may also be necessary to tune some of your web server's settings to improve page speed performance. By and large, tuning page speed does require expertise and is a matter best left to an expert.
1 Akamai, "Performance Matters - 9 Key Consumer Insights" (May, 2015), https://www.akamai.com/us/en/campaign/performance-matters.jsp
Akamai, "state of the Internet Q1 2016 report" (July, 2016), https://www.akamai.com/us/en/multimedia/documents/state-of-the-internet/akamai-state-of-the-internet-report-q1-2016.pdf?mkt_tok=eyJpIjoiWlRWak1HUXpPVE00WVdOayIsInQiOiJpOEJWNXJhcTBNUjVpUXB4WHd6QjV3RDBIUzRYdFo2UklKVDZhckMydlczMTlpRWdnV3daK203Z2JYVzJuOVpOck9QeEE2VXBuTzAxQjlRcW5nMVVnMjR2NzF1SXIydjJjelJ4OEZpY0lkUT0ifQ%3D%3D"
2"Ericsson Mobility Report" (Feb, 2016), https://www.ericsson.com/res/docs/2016/mobility-report/ericsson-mobility-report-feb-2016-interim.pdf
Billy Hoffman on the MOZ blog, "Improving Search Rank by Optimizing Your Time to First Byte", (9/26/2013), https://moz.com/blog/improving-search-rank-by-optimizing-your-time-to-first-byte
Testing for image impact on page speed with Google PageSpeed Insights https://developers.google.com/speed/pagespeed/insights/
3 Marvin Russell, Mysiteauditor.com "20 Signs Your Web Designer is Terrible" (2013), https://mysiteauditor.com/blog/20-signs-your-web-designer-is-terrible/
Rick Viscomi, Andy Davies, Marcel Duran, Using WebPageTest, O'Reilly Media Inc, Sebastapol, CA (2016) ISBN: 978-1-491-90259-7
Like many O'Reilly books, this one is fairly technical. However, it does an excellent job of covering the operation of webpagetest.org.