Why site speed is important for your Shopify store and how to optimize it for more conversions

| By Kelly Vaughn

Why site speed is important for your Shopify store and how to optimize it for more conversions

There are many different factors that influence how customers feel about your Shopify store and their likelihood to make a purchase – your branding, how the page is laid out, your products, reviews, and more. However, before they can even make a decision on how they feel about your store, it needs to load first. 

Page speed is a big deal in ecommerce. Customer expectations around it are growing, so much so that in May 2021 it’s set to become a key ranking factor for Google. This means fast your site loads affects every step of the customer journey from discovery all the way to retention. 

So how does this influence customers throughout their journey, and what can merchants do to make improvements?

How site speed impacts the customer journey

There are a multitude of factors that contribute to the overall customer experience when browsing a Shopify store. Oftentimes in ecommerce we discuss aspects such as the checkout process, product page layout and information, email marketing workflows, personalization and more. Site speed is a growing concern, and it is part of that customer experience. We’re going to discuss its importance as part of that experience, from the point of view of the customer.


The first phase in a customer’s journey is actually discovering that a brand exists. A major way they’re going to find these new brands is through search engines. They’re looking for a specific type of product or service, whether that’s for themselves or a family/friend, and they have transactional intent in their searches. Maybe they’re looking for a new coffee subscription, or they’ve just got into cycling and are looking for a new activewear brand, or a friend’s birthday is coming up and they need to find a gift related to a hobby they’re unfamiliar with. Whatever the case, Google is going to be your best friend in attracting those new customers. 

Google as a service prioritizes the user experience of the platform. The more people use it, the more prolific and successful it is, and the way it maintains its share of the market is by providing users with relevant results that satisfy their search queries. As mentioned earlier, one of the ways it plans to determine the best results is through what it calls Core Web Vitals. These are a set of three factors that essentially combine to measure page speed. Here’s a basic rundown:

Largest Contentful Paint (LCP) - In not-so-technical terms, think of this as loading time - it’s the time taken for a page’s largest piece of content to load in the viewport. The viewport is the page the user sees on their screen without having to scroll. For example, the largest piece of content of a page might be an image - the length of time this takes determines the LCP score.

First Input Delay (FID) - This is the time taken for a page to become interactive, i.e. when the user can start to interact with the page - e.g. clicking links. For example, a store’s homepage loads and you try to click on the menu...but nothing happens. The longer it takes for the page to become interactive, the worse a page’s FID score will be.

Cumulative Layout Shift (CLS) - This measures a page’s stability, in other words the page content doesn’t shift in any significant way. The best way to think of this is you click on a product page, and the image hasn’t loaded yet but as it starts to, the rest of the page’s layout starts shifting to accommodate it. You might try to click on something, but the layout shift means you accidentally click on something else. 

These three factors alongside four other existing factors -  mobile friendliness, safe browsing, intrusive interstitials, and HTTPS - combine to form Google’s new page experience ranking factor for SERPs (search engine results pages). If you’d like to learn even more then check out Google’s own posts about Core Web Vitals and ranking.

In summary, if your page loads quickly then it’ll rank higher in Google SERPs. The higher it ranks in search results, the more likely a customer will be to land on your store. 


Ranking higher is just one piece of the puzzle, the next is in how site speed affects conversions. Let’s say you don’t rank in the top spot, maybe you’re a few down on the page but still high and amongst your competitors. A user navigates to your store, and it takes a while to load. They get tired of waiting, and decide to look elsewhere. When we say tired of waiting, that window of opportunity really isn’t long at all - in fact, the first 5 seconds make the biggest impact on conversions, with conversion rates drop by an average of 4.42% with every second a page takes to load between 0 and 5 seconds. When a site loads within the first second, the conversion rate is around 32% but by the time the first second has elapsed that rate plummets to 20%. 

There are of course many factors that contribute to conversions, however page load speed is undeniably one which has a major impact with more than 70% of customers admitting that page speed does impact their willingness to buy from an online retailer. 


Once you’ve acquired new customers, it’s time to nurture those relationships. Regular, loyal customers are more valuable to your brand than new customers - your probability of selling to a new customer is just 5-20%, whereas selling to a loyal customer your probability rises to 60-70%. So if you’ve already acquired the customer, how does site speed affect their loyalty? The post-purchase phase for a customer is crucial - 79% of customers say that if they’ve had a poor experience due to site performance on a store they’re less likely to make a purchase again. 

However it goes beyond that individual customers, as people share their experiences with friends and family, on social media, and in reviews. Site performance plays an important role in perceived user experience, with 40% of consumers saying they’d share a poor experience with a friend or family member, and 30% saying they’d share a negative experience on social media. On the other hand, 49% say they’d share a positive experience - therefore there is even more incentive for Shopify merchants to provide a great experience.

4 simple ways to improve site speed

Now that we understand how site speed affects the customer journey and experience, how do we actually improve it? There are many changes you can make that will boost page speed, but we’re going to cover 4 ways that you can action right now.

Optimize on-page content

It may sound obvious to say “optimize your content”, however sometimes the most obvious solutions are some of the best. It’s also one of the easiest solutions to implement that can make a big difference. There are a few ways you can optimize your content to impact page speed:

  • Save images for web to minimize their file size - this compresses them without sacrificing quality
  • Define image dimensions within the page’s code - this will help to minimize CLS (Cumulative Layout Shift)
  • Be selective with images - the more images, the longer it will take to load the page. 

Review app usage

Apps are great for your store, and with thousands available in the Shopify App Store that cover everything from loyalty programs to order tracking to inventory management, you’ll undoubtedly be using a few already. However these apps running in the background of your store can affect your site performance and slow it down. Review all the apps you currently have installed, and remove any that are deemed unnecessary. It might be that you installed one to test it out and forgot to remove it, or you have something installed that was once useful but your store has outgrown its usefulness. Then in the future, be very selective with how many new apps you add to your store.

Spring clean your links

Broken links are a pain for your store visitors. Not only that but broken links for page elements can impact your page’s load speed. There are two fixes here - the first is related to customer experience in finding a broken link, and that is to create a custom 404 page that can redirect them to other pages on your store that they may be looking for. The second is to either fix or remove broken links for page elements.

Eliminate hero images

Carousels and sliders with big high quality images of your products on your homepage sound like a great idea. They can show off a few of your products and offers in one place, and they look pretty good. However they take a long time to load, and can really eat into your page load speed, especially on mobile. Therefore on both desktop and mobile we would recommend selecting just one that encapsulates your brand, swapping it out as required if you have new products or a sale.

If you’re not convinced based purely on the impact on site speed, then they also aren’t all that useful when it comes to conversions and promoting your products. A study by Nielsen Norman Group found that carousels are more often than not ignored by customers and can cause frustration. A different study found that the click through rate (CTR) on carousel images was less than 1%, with 84% of the clicks occurring on the first slide.


Competition in the ecommerce industry is tougher than ever, and the merchants who provide the best customer experience will be the ones to come out on top. Site performance is just as important as the quality of your products when it comes to that experience, so by ensuring you’re optimizing for speed you’ll provide customers with a positive experience that keeps them coming back for more.

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