Why is my Shopify store so slow? (and how to find out)

If your Shopify store feels sluggish, it’s almost always one of a few usual suspects. Here’s how to find the culprit.

The usual suspects

1. Big, unoptimised images. The single most common cause. A few oversized product or hero images can add seconds on their own.

2. Too many apps. Every app injects CSS and JavaScript that loads on every page — even pages the app never touches. A store with 20+ apps is almost always slow.

3. A heavy theme. Some themes ship with bloated code, sliders, and effects you don’t use. A lean theme is the easiest long-term fix.

4. Third-party scripts. Chat widgets, popups, reviews, trackers — each is an external request that can stall your page.

5. Render-blocking resources. Fonts and scripts that load before content delays the first paint.

How to find which one

Don’t guess. Run your store through the free page speed test — it reports your real score and load time, so you know whether you have a problem and roughly how bad it is. Then work the fixes in order of impact (images and apps first).

Mobile is where it shows

A store that feels fine on your office wifi can be painfully slow on a phone over mobile data — which is where most shoppers are. Always judge by the mobile result.

Fix it, then watch the rest

Once you’ve found and fixed the slowness (see how to speed up your Shopify store), remember speed is one of several revenue leaks. To see them all — speed, conversion, checkout, AI visibility — in one score, use Revyfix.