24 October 2023

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Optimising eCommerce Website Speed for Better Conversions

When trying to obtain higher conversions, website speed can make a huge difference. The impact of website speed on conversion rates can be seen clearly when we look at the data. According to a report by the Aberdeen Group, “every 1 second delay in the page load time reduces customer satisfaction by 16%, page views by 11% and conversion rate by 7%.” In an industry where customer satisfaction is paramount, how do ecommerce companies ensure their site is up to speed? 


Choosing the Right Platform

One of the ways many businesses might try to cut costs is by opting for a budget web server, however the effect this has on your site’s performance could be detrimental to your conversion rates. Cheaper host sites often cram as many websites as possible onto one server, meaning the speed of your site usually suffers as a result. Because of this, it’s important to work out your budget before choosing a server to ensure you’re getting the best platform for your site that you can afford. As well as budget, there are a number of technological factors that might influence which web server you choose. 

Here at 5874 Commerce, we pride ourselves on delivering the perfect platform for our ecommerce clients. For example, fashion brand Mona came to us looking for a modern, agile platform and solution environment to ensure their site long-term growth and stability. In this instance, we knew that Ionic React and our ecommerce partner BigCommerce should be the platforms of choice for this particular build. Using our team’s expertise and 5874’s partnerships with Vercel, Linnworks, Klaviyo and WordPress, we were able to deliver Mona Online with the perfect tech stack that was tailored to their site’s needs. As a result of this, the business saw a boost in conversions and revenue as it received upwards of 3,000 orders, 52,000 users and a High Google Lighthouse score. Through this data, we can see that choosing the correct platform and integrations is key to maximising a site’s potential in terms of speed and conversions. 


Optimising Web Page Weight

The average web page weight is constantly increasing due to unmeasured and unoptimised assets, with site speed suffering as a direct result. According to data collected by HubSpot, “In 2020, the average desktop webpage weighs 2080 KB, while the average mobile webpage weighs 1885 KB — this is a stark difference from 2017, when an average desktop webpage weighed 1532 KB and the average mobile webpage weighed 1354 KB.” So how do we lighten the load? Well, according to Google’s own researchers, “Graphic elements like product images and logos regularly make up nearly two-thirds of product web page weight.” Therefore, limiting images and ensuring file sizes are only as large as they need to be is essential when trying to reduce web page weight. For example, BigCommerce suggests “resizing images and making sure the images have a low byte size will increase the speed of the page.” In addition to this, BigCommerce uses ‘Responsive Images’ that automatically optimise images, thus helping to offload some of this work. 


Compression is Key

In addition to limiting graphic elements on your website, compression is a great way of ensuring that the essential files on your site are properly optimised. The most efficient way to do this is enabling a compression algorithm that compresses files before they reach the user’s browser. Gzip is one of the most widely supported compression algorithms, while Brotil boasts the best compression ratios and speedier decompression overall. Here at 5874, we also leveraged both Gzip and Brotil for our client, Mona, to compress JavaScript files to successfully optimise their website. Compression can be easily utilised by modifying the configuration file or simply using plug-ins and tools that do all the work for you. Both Gzip and Brotil can be integrated into your website using Vercel’s Edge Network and implementing one of their two compression algorithms.


Leveraging Browser Caching

Browser caching allows elements of your site to be temporarily stored in the visitor’s browser. By leveraging browser caching, you’re reducing the need for files to be redownloaded, significantly minimising loading time and boosting conversions. In addition to this, bandwidth consumption is reduced and SEO is improved, which ultimately leads to a better user experience overall. Expires and Cache-Control headers can also be used to set a maximum age and validation of your cached files, therefore ensuring that your cached data is always fresh and up-to-date. Caching can also be utilised easily by integrating Vercel’s Edge Network, either with static file caching or using their Cache-Control headers for dynamic content, including SSR content. 


The Importance of Site Speed Testing

In order to maintain the best website performance, it’s important to conduct regular speed tests. Through these tests, you can measure load times and see what elements contribute to your site’s overall speed score. One of the most efficient ways to test your site’s performance is by integrating our partner, Vercel, and enabling their Speed Insights. Vercel’s Speed Insights “provides you with a detailed view of your website’s performance metrics, facilitating informed decisions for its optimization.” 


As well as providing you with a Real Experience Score (RES) which gives a clear overview of your site’s performance at the time of the test, Vercel’s Speed Insights also offers a Virtual Experience Score (VES) which predicts and anticipates the impact of your site’s current performance. Increased RES and VES scores translate to a better end-user experience, and therefore better conversions. The RES and VES (along with Core Web Vitals) are colour-coded for ease of interpretation, with red being Poor (0 to 49), orange being Needs Improvement (50 to 89) and green being Good (90 to 100). Although achieving a score of 100 is extremely difficult, sites should strive for a ‘Good’ rating to ensure optimal user experience. Whether your site is scoring very low or closer to 100, site speed tests will point you in the direction of the problems that are causing your website to lag behind. Once you know the correct course of action, you could unlock the key to a speedier website and as a result, an uptick in conversions. 


There are a number of reasons why your website isn’t securing the conversions you want, but slow loading times is one of the most common and one of the easiest to rectify. So, here are the key takeaways:


  • Make sure you’re choosing a server that is the most beneficial for your website
  • Drop the weight from your site by eliminating unnecessary graphic elements such as images and custom fonts
  • Optimise the graphic elements that are necessary for your website by leveraging compression
  • Utilise browser caching to minimise loading time and boost conversions
  • Take advantage of site speed testing (like Vercel’s Speed Insights) in order to check your site’s performance and identify any problems that are hindering your conversion rate


As ecommerce experts and certified partners of BigCommerce and Vercel, we want to help you optimise your site and maximise conversions. Take a look at our partner network to learn more about how our developers at 5874 can digitally transform your business with the help of our partnerships.




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