Why Is My Shopify Store Slow? How to Find the Cause and Speed It Up

A slow Shopify store is almost always caused by four things: too many apps loading scripts, oversized images, a heavy theme or theme customizations, and third-party code like chat widgets and tracking pixels. Shopify's hosting itself is rarely the problem, so the fix is usually removing or trimming what you added.

Here is how to measure it, find the cause and fix it.

Measure first: the speed report and PageSpeed Insights

Don't guess. Get two readings before you change anything:

- Shopify's own report. In the admin, go to Online Store → Themes. Depending on your admin version you'll see a speed score or a link to the web performance report (also under Analytics → Reports). It is based on real visits to your store, so it reflects what customers actually experience. - PageSpeed Insights. Open pagespeed.web.dev and test three URLs: your homepage, a collection page and your best-selling product page. Look at the mobile tab first; most shoppers are on phones and mobile scores are usually lower.

In PageSpeed, focus on Google's Core Web Vitals: Largest Contentful Paint (how fast the main content appears; Google calls 2.5 seconds or less good), Interaction to Next Paint (how fast the page reacts to a tap) and Cumulative Layout Shift (how much the page jumps while loading). Write down the numbers so you can compare after each change.

Apps: the most common cause

Many apps add JavaScript to every page of your store, even pages where they do nothing. Ten apps can mean ten extra scripts on your product pages.

- Go to Settings → Apps and sales channels and list every app. For each one, ask: do I still use this, and does it earn its place? - Uninstall the ones you don't need. - Check for leftover code. Some older apps inserted code into your theme files and don't remove it on uninstall. In Online Store → Themes → … → Edit code, look in `theme.liquid` for script tags or `{% render %}` lines that mention apps you removed. If you're not sure, duplicate the theme first or ask the app's developer. - In the theme editor, open App embeds and switch off any embed you don't use.

Remove apps one at a time and re-test, so you know which change helped.

Images: big files, small screens

Shopify serves images through its CDN and resizes them for different screens, but a theme section can still load a much larger image than it needs, and huge uploads slow down editing and some themes.

- Before uploading, resize photos to a sensible size. Around 2,000 pixels on the longest side is plenty for most product zoom; banners rarely need more than that width. - Compress them. A photo straight from a camera or phone can be several megabytes. - Avoid autoplay videos and large sliders in the first screen of the homepage. One strong image usually loads faster than a carousel of five.

Your theme and its customizations

- Update your theme. Theme developers ship performance fixes. In Online Store → Themes, check whether a newer version is available, and test it as an unpublished copy first. - Remove sections you don't use from the homepage. Every section and feed adds work. - Watch custom code. Snippets pasted in from tutorials or old freelancers often load extra libraries. If your store got slow after a specific change, that change is the first suspect. - Limit fonts. Each extra custom font or weight is another file to download.

Third-party scripts

Chat widgets, pop-ups, heatmap tools and several tracking pixels all compete for the same load time. Keep the ones you actually look at. If two tools do the same job, keep one. Where possible, add pixels through Shopify's customer events (Settings → Customer events) instead of pasting code into the theme.

EcomBoost AI scores your store's health and finds problems that cost sales, such as products priced at $0, sold-out products still listed, duplicates and products missing descriptions or images, then fixes many of them in one click instead of leaving you a to-do list. Want to see what it finds? [Check your store free](/free-store-check).

Frequently asked questions

### What is a good speed score for a Shopify store?

There is no single number that guarantees sales. Compare your store with itself over time, and use Google's Core Web Vitals thresholds as the target: content that appears in about 2.5 seconds or less on mobile, quick response to taps and little layout shift.

### Do Shopify apps slow down my store?

Many do, because they load scripts on every page. Apps that only work in the admin usually don't affect the storefront. The way to know is to remove an app you don't need and re-test.

### Why is my PageSpeed score different every time I test?

PageSpeed runs a simulated test, and results vary with network conditions and server load at that moment. Run it two or three times and look at the trend, and give more weight to the real-visitor data in Shopify's report and in PageSpeed's field data section.