How to Eliminate Render Blocking Resources in Shopify for Faster Pages

One of the most important factors in today’s digital world is website speed – user experience and ranking in search engines. However, slow pages are frustrating for visitors as well as may impact the site’s efficiency. Among the primary causes of slow page loading is render-blocking resources that significantly slow up the page-load time it takes to be visible to users.

We begin learning to remove render-blocking resources in Shopify so that your pages are going to load faster. We will learn what the render-blocking resources are and what their importance is. Then, we will discuss some ways to optimize CSS and JavaScript in order to arrive at better performance. Finally, we will discuss measuring and monitoring improvements in speed of your site. By the end of this course, you would be able to make your Shopify store load faster by putting the learned knowledge into action.

Understanding Render-Blocking Resources

What are render-blocking resources?

Render-blocking resources are file types that prevent a browser from rendering the content of any page immediately. Generally, some of those files that a browser has to fetch and execute before any element is rendered on-screen include CSS and JavaScript files. Webpage fetching encompasses reading through HTML code in sequence line by line by a browser. If it scans the complex scripts and tags in the section, then it should apply them before it continues reading from the page.

How they impact page load speed

Resources like blocking paint will make it load your website quite slowly. They delay something called the First Paint, whereby for the first time your browser displays something on the screen, whether it’s background colors, borders, or text images. And these delays may make the visitors feel that your site is taking too long to load, and some might refresh the page; others even go back or leave your website completely.

With many render-blocking resources, visitors will wait in front of a blank screen for a long time before even any content starts loading. Such a situation will undoubtedly harm user experience. It is more preferable that the page loads incrementally because it gives the view that it is a faster site even though the actual time span of loading doesn’t change.

Common render-blocking resources in Shopify

In Shopify stores, the most common source of render-blocking resources is actually your top-positioned JavaScript and CSS files. These are parts of what’s known as the critical rendering path-the way that a browser takes your code and renders it into the visual experience users see on their screens.

Common render-blocking resources in Shopify

Here are some specific examples of render-blocking resources in Shopify:

  1. CSS files: Stylesheets that don’t have a ‘disabled’ attribute or a ‘media’ attribute matching the user’s device can block rendering.
  2. JavaScript files: Script tags in the of the document without a ‘defer’ or ‘async’ attribute will block rendering.
  3. HTML imports: These can also block rendering if they don’t have an ‘async’ attribute.

The browser knows absolutely nothing about how such files might impact the rest of the page, so it freezes everything and waits for those to download and use before continuing. This happens one file at a time, which in practice might prolong more than is needed.

Note that, importantly, not all resources of this type are actually render-blocking. Consider, for example, a script with an ‘async’ attribute: it won’t block rendering. Yet some resources might be more important than others. Resources that load above the main page heading are likely to stall the fast presentation of important content very likely indeed.

Understanding what render-blocking resources exactly are forms the first step in your way to improving your Shopify store’s speed. In the following chapters, we’ll talk about optimizing CSS and JavaScript, as well as minimizing their impact on the loading time of your page.

Optimizing CSS for Faster Rendering

CSS is important to how your shop looks and how it works within Shopify. It makes your site look pretty, but when done wrong, it slows the pages. Let’s take a look at some ways to improve your CSS so that your pages will load a little faster.

Identifying critical CSS

Critical CSS are those styles required to load above the fold content visible to a visitor if viewed for the first time on your site and also noticed even before scrolling down. This would be dealt with finding and focusing on this particular CSS so that the page may load up quicker at the beginning.

Critical CSS are those styles required to load above the fold content visible to a visitor if viewed for the first time on your site and also noticed even before scrolling down. This would be dealt with finding and focusing on this particular CSS so that the page may load up quicker at the beginning.

Inlining critical CSS

Now that you’ve pinned down your critical CSS, it’s time to inline them. You place these styles in direct relationship with the head of your HTML document. This way, all that the browser has available is direct access to all the styles it may need for the first round of rendering without its having to wait for the loading of external CSS files.

To inline critical CSS in Shopify:

  1. Create a new file called ‘critical.css.liquid’ in your theme’s snippets folder.
  2. Paste your critical CSS into this file.
  3. In your theme.liquid file, add the following line in the section:

{% render ‘critical.css’ %}

This approach allows the browser to start rendering the page faster, improving the perceived load time for users.

Deferring non-critical CSS

After inlining critical CSS, you’ll want to defer loading of non-critical styles. This prevents these less important styles from blocking the initial render of your page.

To defer non-critical CSS:

  1. Move your main CSS file reference to the bottom of your HTML, just before the closing tag.
  2. Use the following code to load your CSS asynchronously:

<link rel=”preload” href=”{{ ‘theme.css’ | asset_url }}” as=”style” onload=”this.onload=null;this.rel=’stylesheet'”>

<noscript><link rel=”stylesheet” href=”{{ ‘theme.css’ | asset_url }}”></noscript>

This preload attribute is to be used to preload the CSS file so that it doesn’t delay rendering but instead applies when it’s loaded.

Such techniques always help decrease the download time involved in relating the initial content of a Shopify store to any great extent. This in turn gives better user experience and may eventually result in the engagement and conversion rates.

First, begin by focusing on delivering the most important styles in time, moving the less-important styles to be implemented post-first-page-render. This will ensure that your pages look great while ensuring higher speed of loading, therefore providing the best experience for customers in your Shopify store.

Optimizing JavaScript for Performance

JavaScript is pretty crucial to make any website look interactive and dynamic. But if it’s not well controlled, it’s probably slowing up your Shopify store. Here are a few good ways to improve JavaScript for better performance.

Auditing and removing unused JavaScript

First, unwanted codes and unused codes must be removed. Unused numbers of JavaScripts may slow the page loading speed, expand the bandwidth, and even reduce your rank on the search engines. It is always a good idea to scan through your usage of JavaScript using tools such as Google Lighthouse, Chrome DevTools, or WebPageTest, which may give a line-by-line breakdown of used and unused codes within each script file.

After you discover JavaScript you’re not using, remove it from your theme code. This might mean entirely removing whole files or commenting sections of code. Be careful while removing code, as some may be needed to achieve certain functions. If you are unsure about a particular script, check to see if it is associated with an app you have installed or is an outside service.

Regular audits must be conducted to keep the JavaScript at its best. Set regular checks, most importantly after installing or uninstalling apps or after huge changes within your store functionality.

Deferring non-critical scripts

Deferring non-critical scripts is an effective way to improve your store’s loading speed. By using the ‘defer’ attribute, you tell the browser to continue parsing and rendering the HTML without waiting for the script to download and execute.

To implement this, add the ‘defer’ attribute to script tags in your HTML:

<script src=”non-critical-script.js” defer></script>

This is very useful for scripts that do not necessarily have to run at page load. For instance, you can delay scripts whose pages may run lower or are started through user actions.

Asynchronous loading techniques

Some of the important resources, like scripts, will load in the background while the rest of the page loads. That can greatly reduce the total time-to-load for a page.

To load scripts asynchronously, use the ‘async’ attribute:

<script src=”async-script.js” async></script>

The ‘async’ attribute lets the browser download that script in the background while continuing to render the page; it waits for the script to be loaded and then executes it.

But note this only works with some scripts. For instance, where a script relies on others, or should be run in an order other than that more natural order in which it occurs, this fails. At times you will have to make use of the ‘defer’ attribute or another option to optimize it.

Use these sparingly, testing your site carefully to make sure everything is working as intended. Asynchronous or deferred loading sometimes doesn’t play nicely with specific plugins or themes.

Also, being on the lookout for unused JavaScript makes it delay unnecessary scripts and use asynchronous loading methods to really speed up your Shopify store. That’ll give you improved load times across pages, a better experience for users, and perhaps even improved search engine ranking.

Measuring and Monitoring Performance

Monitoring your shop’s health on Shopify is one important factor in having a fast and fluid website. Use this tool by regularly searching for problems you can address right away. Now, let’s see some good tools and methods in doing so.

Measuring and Monitoring Performance

Using Chrome DevTools

Chrome DevTools is an integrated feature of the Google Chrome web browser that might make your life easier in testing the performance of your website. Inside Chrome DevTools, there is something called the Performance Monitor, which represents these front-end performance metrics in a very fast real-time visualization: CPU usage, JavaScript memory usage or JS Heap Size, DOM Nodes, and Layouts per second.

Now, open Chrome DevTools either by Ctrl + Shift + I or Cmd + Option + I if you have a Mac. Now, open the Command Menu using the shortcut keys Ctrl + Shift + P for Windows users and Cmd + Shift + P for Mac users. Navigation to and opening the Performance Monitor.

This tool is pretty handy because it stays active even as you’re flipping between pages. That lets you see how the numbers change as users use your site-for example, you could watch CPU usage go up and down as a customer buys something or check for JavaScript memory increases as they fill in forms.

Leveraging Lighthouse audits

Google Lighthouse is a free tool to improve your web site. It will provide detailed reports on different parts of the performance of your website, namely speed, mobile usability, and Core Web Vitals.

All the methods available can be used with Lighthouse: Chrome DevTools, as a Chrome extension, or directly in the Node.js command line. Once running an audit, Lighthouse generates a report reflecting the overall score for the page, each individual audit scores, performance metrics, and ideas about improvement.

The report is divided into several categories:

  1. Performance: Evaluates loading speed, interactivity, and stability.
  2. Accessibility: Assesses how user-friendly your site is, especially for users with disabilities.
  3. Best Practices: Checks if you’re following recommended web standards.
  4. SEO: Analyzes your site’s search engine optimization.
  5. Progressive Web App (PWA): Evaluates your site’s ability to offer app-like experiences.

Pay special attention to the opportunities and diagnostics sections, which provide specific suggestions for improving your site’s performance.

Ongoing performance tracking

Keeping track of performance in an ongoing manner is very crucial for maintaining over time the continuous optimal performance of your Shopify store. For this purpose, Shopify provides the Web Performance dashboard as a useful tool. It provides information, drawn from real-user data, for the last 28 days, measuring your store against the three Core Web Vitals: loading speed, interactivity, and visual stability.

It includes a line chart, showing the effect on each of your store’s Core Web Vital changes-it shows changes your store had with installed apps, updated themes, or introduced new code at any time. Filters include time range, date grouping, and devices for best fitting the traffic patterns of your site.

The number of page visits in each performance category-good, moderate or poor-is then represented graphically with a bar chart. This will help you to see how general user experiences vary between devices and kinds of connections.

Remember that it could take some time for the changes made internally in your store to trickle through into performance metrics. Ultimately, it’s a good idea to keep the Web Performance dashboard refreshed weekly to catch problems before they have an impact on conversions and SEO.

All these tools and methods used frequently will ensure that your Shopify store not only remains fast and responsive but also easy for the customer experience as well as business results.

Conclusion

Reduce render-blocking resources and improve your Shopify store. This contributes to how fast the pages will actually load and what users are going to think of their experience. Important CSS may be delayed, non-important scripts queued, and asynchronous loading implemented to improve the performance significantly. In that process, you are not only creating a superior user experience but also impacts in terms of search rankings and conversion rates.

The best way to ensure that your store continues working well is to monitor and track the performance of your Shopify store very often. You might be using Chrome DevTools and Google Lighthouse, which provide great information for investigating your website speed and locating improvements. Always working on improvements will make sure that your Shopify store is fast, responsive, and easy to use-they will lead to happy customers and better business results, of course.