Improving your online store 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 performance. Some features can slow down your site or create unexpected behaviors that can impact user experiences.

Web performance focuses on optimizing user experience. Currently, web performance focuses on three major areas which are also reflected in the Core Web Vitals:

• Loading speed, measured by Largest Contentful Paint (LCP)
• Layout stability, measured by Cumulative Layout Shift (CLS)
• Responsiveness to user interaction, measured by First Input Delay (FID) and Interaction to Next Paint (INP)

Optimizing web performance means that your customers are more likely to stay on your site and convert. Learn more about why web performance matters.

Optimizations for your online store

Your online store has web optimization built into it. Web optimization is also built into any new features. You don’t need to do anything special to take advantage of the following features:

• Your online store is hosted on fast, global servers and doesn't limit your store's bandwidth. You can check the status of your Shopify store on Shopify Status.
• Your online store has a content delivery network (CDN) run by Cloudflare that ensures that your online store loads quickly around the globe. You can check the CDN status on the Cloudflare status page.
• To keep load times fast, images are automatically optimized using image CDN. Combined with your theme code, the image CDN can serve the best image format that's also resized and compressed to keep file sizes small.

Factors that impact web performance

For Shopify stores, the following are the biggest factors that impact web performance:

• Your online store theme
• The apps you’ve installed
• Any additional third-party code you’ve manually added to your store, including tag managers and the tags within them

This means that you should focus on the following to improve your web performance:

• Use an up-to-date, optimized Online Store 2.0 theme. All Online Store 2.0 themes by Shopify are free and optimized for web performance. Additionally, many other third-party themes are also optimized for web performance. You can review the latest theme performance data.
• Evaluate your installed apps and third-party code to ensure that they're creating enough value to offset any potential performance losses.
• Audit your tag manager to remove any unused or low-value tags. Learn more about best practices for tags and tag managers.

Testing tools

You can use the following tools to investigate your online store's performance.

Web Performance dashboard

Shopify's Web Performance dashboard report uses Core Web Vitals to measure how real users experience your online store.

PageSpeed Insights

You can run your own reports using Google's PageSpeed Insights to view more detailed metrics for pages in your store.

Get support with online store performance

If you use a free theme from Shopify, then Shopify Support might be able to assist you with basic performance improvements.

If you use a third-party theme and need assistance, then you must contact your theme developer, hire our Shopify web performance experts, or hire a Shopify Partner. Learn more about hiring a Shopify Partner.

If your performance problem is coming from an app, then you can contact your app developer.

If you have a development team or agency partner, then you can also reach out to them for further assistance.

Technical information and resources for troubleshooting

If you’re a developer seeking to improve performance for a Shopify storefront, theme, or app, then you can review the following resources for each Core Web Vital. Learn more about performance best practices for Shopify Themes.

Loading speed

Largest Contentful Paint (LCP) measures loading speed, based on how fast the largest element on the screen becomes visible. Time to first byte (TTFB) and first contentful paint (FCP) are supporting metrics which help you better understand where the root cause of the problem is coming from. You can learn more about debugging common causes for slow loading in Shopify Liquid storefronts.

Visual stability

Cumulative Layout Shift (CLS) measures visual stability, based on how much the content shifts around unexpectedly during loading. For a deep-dive on debugging CLS, read How to optimize Cumulative Layout Shift (CLS) on Shopify sites.

Interactivity

First Input Delay (FID) measures interactivity, based on how long it takes the page to become responsive to the first user action, such as clicking a link or a button. It was replaced by Interaction to Next Paint (INP) in the Core Web Vitals, and we’re working on adding INP to the Web Performance dashboard.

If you’re suffering from poor FID or INP, then most likely you have too much JavaScript in your store from either theme code, app code, or third party/tag manager code. Work on cleaning up your worst offenders. Learn more about 3 ways to find your worst JavaScript offenders for page load. If you’re still having issues with INP, then learn more with the resources on web.dev.