Improving the performance of your store
We often receive requests on how the performance of stores can be improved. Store speed is a shared result of many moving parts on your Shopify storefront. While your theme plays an important role, you will generally see that most performance issues come from third-party apps, oversized media, custom code, or platform-level factors outside the theme’s control. This article explains what affects your speed, what you can check, and how you can improve real-world performance.
How Shopify Measures Speed
Shopify’s speed score is based on Google Lighthouse tests running on a replica of your homepage. These tests simulate conditions that don’t match real customers and can fluctuate daily. You may sometimes see lower scores even when your store feels fast to actual users.
Factors That Commonly Slow Stores Down
Apps and third-party scripts
Apps are the number-one cause of slow stores. Many apps load their own CSS, JavaScript, tracking scripts, and external resources. Even after uninstalling an app, leftover code snippets may remain.
Oversized images and videos
Large hero slideshows, uncompressed images, GIFs, or background videos increase loading time. Shopify recommends keeping images under 300–500 KB whenever possible.
Custom code changes
Injected HTML, unused JavaScript libraries, and poorly optimized customizations can slow pages down. If your codebase was modified by multiple developers over time, the result can be a heavy theme file.
Excessive apps running on page load
Upsell apps, reviews widgets, chat widgets, tracking pixels, and personalization tools often run immediately when a page loads. Each additional request compounds total load time.
Large product catalogs and complex collection filtering
Huge menus, mega-collections, and aggressive filtering options can create heavier page structures.
Network and device conditions
Speed scores use simulated throttled network conditions that don’t always reflect what your customers experience. A slow device or slow connection also impacts the results.
What You Can Do to Improve Speed
Remove or replace heavy or unused apps
Review your app list and remove anything not essential. If a feature is optional, consider a lighter solution or built-in theme option. We always suggest making regular backups of your theme, especially if you will be trying out different apps.
Compress images
Upload images at the correct size. Tools like TinyPNG or Shopify’s built-in compression help reduce file weight.
Limit the number of apps running above the fold
Move pop-ups, chat widgets, and reviews to load after the first interaction when possible.
Check for leftover code
After removing apps, open the Online Store > Edit Code panel and check snippets, templates, and theme.liquid for unused scripts. Simply removing an app does not always remove its code. Therefore, we always suggest checking with the app's support site to make sure you have followed full uninstallation instructions.
Reduce homepage weight
Limit autoplay videos, remove large carousels, reduce the number of featured products, and simplify homepage sections. A clean homepage loads significantly faster.
Test with Shopify’s Analyzer
Use Shopify’s recommended tools, such as:
- Shopify Speed Score: Online Store > Themes
- Lighthouse via Chrome DevTools
- PageSpeed Insights
- Shopify’s Theme Inspector for Liquid: https://shopify.dev/docs/themes/tools/theme-inspector
These tools highlight code bottlenecks, large assets, and JavaScript sources.
Check app loading behavior
Some apps allow you to delay their scripts until user interaction. This can improve LCP and FID scores.
What We Do as a Theme Developer
We design our themes to be as fast and lightweight as possible. Your theme does not include unnecessary libraries, unused scripts, or bloated animations. Our templates follow Shopify’s strict performance guidelines, and any dynamic loading options (lazy loading, optimized images, structured data, modern CSS practices) are built-in by default.
Because store performance depends on the full environment, not just the theme, real-world speed is influenced heavily by the apps, media, and customizations added afterward.
When to Contact Us
If you have removed unused apps, optimized your images, and simplified your homepage but are still seeing issues, contact us through theme support. We are happy to:
- Explain what is theme-related versus app-related
- Check if your theme version is up to date
- Suggest lighter alternatives to heavy design choices
We want your store running as smoothly as possible, and we’re here to help you identify what will have the biggest impact.