Online store Web Performance

Your online store Web Performance dashboard measures loading speed, interactivity, and visual stability. These measurements help you understand how your vistors experience your website from when the page first loads to layout shifts that might be caused by pop-up content.

How is web performance measured?

Web performance is measured by key metrics called Core Web Vitals.

The Core Web Vitals include the following performance measurements:

  • Largest Contentful Paint (LCP): measures loading speed, based on how fast the largest element or main content becomes visible to visitors. A good LCP score is achieved when the main content is loaded within 2.5 seconds from the start of the page load.
  • Interaction to Next Paint (INP): measures interactivity based on how long it takes the page to become responsive to most user actions. For example, user actions such as clicking a link or a button. An INP score of less than 200 milliseconds is considered a good performance as the page becomes interactive quickly.
  • Cumulative Layout Shift (CLS): measures visual stability, based on how much the content shifts around unexpectedly during loading. A CLS score of less than 0.1 is considered a good performance.

In addition to the Core Web Vitals, Google evaluates other factors such as mobile compatibility, safe browsing, HTTPS security, and the absence of intrusive interstitials, which are page elements that obstruct a complete view of the content, such as promotional pop-ups or age verification. These factors together help evaluate a webpage's performance and user experience.

Why is web performance important?

Your online store’s performance can impact the shopping experience of your customers, your conversion rate, and your store's discoverability.

Experience and conversion

When your online store loads quickly and interactions are smooth, it provides a positive experience to all visitors regardless of their device or connection speed. If a site is slow or difficult to navigate, then visitors are more likely to leave before they buy something. By improving your store's web performance, you can enhance user experience and increase conversion rates.


Search engines such as Google use page speed as a ranking factor. If your online store pages perform poorly across the Core Web Vitals, then they might be ranked lower, even if your store is otherwise optimized for search engines. By improving web performance, you're improving your store's chances of being ranked higher in search and getting more visibility for your business.

Online store features vs. web performance

Your online store is made up of a set of features, such as theme code, apps, images, videos, carousels, social media feeds, and analytics. These features can enhance the visitor experience and extend your site's capabilities.

However, each feature that you add to your online store can impact your store's Core Web Vitals. Some features can slow down your site or create unexpected behaviors that can impact user experiences.

When you consider adding a feature to your store, you should weigh the benefits of the feature against its impact to the Core Web Vitals. You might need to find the balance between user experience and web performance.

Ask yourself the following questions when considering features for your store:

  • What will help customers make the decision to purchase from the store?
    • For example, consider whether your customers would prefer a simple homepage with links to detailed product pages, or a more powerful home page where they can quickly view and buy products.
  • What functionality should exist at the top of the page to drive conversion?
    • For example, branding elements, featured images, and a checkout cart are all features that can impact performance but increase conversion.
  • What functionality can load later as customers scroll down the page?
    • For example, analytics and product reviews don't need to be loaded immediately when a customer visits your store. You might need to consult your theme or app developers to understand if a feature is loading right away.

Explore your Web Performance dashboard

You can learn how your store performs across the Core Web Vitals by viewing your Web Performance dashboard. This dashboard displays how your store ranks across all three core web vitals and provides actionable insights for improving.

You can also explore factors that impact your web performance and how to address them.

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