Speed Up a Shopify Store: Themes, Apps, Images
By CodexierPublished 5 min read
Shopify hosts your store on a fast, global infrastructure, so a slow Shopify store is almost never a hosting problem. It is the accumulated weight of apps, theme sections, images and third-party scripts added over the years. This guide explains how to measure the store properly and fixes the causes in the order that usually gives the biggest improvement for the least work.
Measuring a Shopify store properly
The speed score in the Shopify admin is a rough average and moves with things you do not control. Use it as a trend, not a diagnosis. For a real picture, run PageSpeed Insights on each of the four templates above, look at the field data for real Swedish visitors if there is enough traffic, and note Largest Contentful Paint and Interaction to Next Paint. Our Core Web Vitals guide explains what each number means. Always test on mobile, because that is where most shop traffic comes from and where heavy scripts hurt most.
App scripts and leftovers
Every app that changes the storefront adds code: a script, a stylesheet, sometimes a block of HTML in the theme. Modern apps use theme app extensions, which Shopify removes cleanly when you uninstall. Older apps paste code into theme files, and that code stays after the app is gone, still loading and sometimes throwing errors on every page.
- List every installed app and mark what it does on the storefront. Uninstall anything nobody can explain.
- Search the theme code for the names of apps you have removed. Remove leftover snippets and their includes, on a duplicate theme first.
- Check for apps doing the same job twice, such as two review widgets or two popup tools.
- Prefer apps that use theme app extensions and load only on the templates where they are needed.
- Publish the cleaned duplicate, then measure again.
Theme sections and sliders
Themes offer many sections, and it is tempting to use all of them. A home page with a slider, a video, three product carousels, an Instagram feed and a newsletter popup loads a lot of code before the visitor sees anything useful. Sliders are the worst offender: they load several large images, the visitor rarely sees beyond the first, and the text on later slides is often ignored.
| Section | Cost | Faster alternative |
|---|---|---|
| Hero slider | Several large images and a script | One static image with a clear headline |
| Autoplay background video | Heavy file, delays the main content | A poster image, video on tap |
| Multiple product carousels | Many images and scripts | One grid of best sellers |
| Instagram feed | Third-party script and images | A few curated photos uploaded to Shopify |
If your theme is several years old and built before Shopify's Online Store 2.0, moving to a current theme often gives more than tuning the old one.
Product and collection images
Shopify's image service converts images to modern formats and resizes them on the fly, but only if the theme asks for the right size. Upload images at a sensible maximum, around the width of the largest display in your theme, rather than straight from the camera. Check that the theme uses responsive image tags, that images below the fold load lazily and that the main product image does not. Keep a consistent aspect ratio in collections, so the page does not jump as images load.
Fonts, video and third parties
The last layer is everything loaded from other services. Custom fonts in several weights, embedded video players, chat widgets, review platforms, and tracking tags for ads each add requests and main-thread work. Keep to one or two font weights, use Shopify's font library where possible, load chat only after interaction, and run tracking through Shopify's customer events rather than tags pasted into the theme.
When you do not need help: a store on a current theme with a handful of well-built apps is usually fast enough, and the checklist above is a morning's work you can do yourself. When the store is years old, has dozens of apps and the product pages feel slow on a phone, our conversion and checkout optimisation includes the speed work alongside the checkout. See the pricing page or book a call to go through your store together.
Frequently asked questions
Will a faster Shopify store sell more?
Speed removes a reason to leave, especially on mobile, but it does not create demand. It matters most on product and collection pages. Fix speed together with product page content and checkout friction, and measure conversion rather than the speed score.
Can we switch to a faster Shopify plan?
The Shopify plan does not change storefront speed in any meaningful way. Hosting is the same infrastructure. Speed comes from what the theme and apps load.
Is it safe to delete code from the theme?
Only on a duplicate theme. Duplicate the live theme, make changes there, preview every template, then publish. Keep the old theme as a fallback for a few weeks.
Why is our speed score different every time?
Lab tests vary with network, location and whatever third-party scripts return at that moment. Run each test a few times and compare trends, and rely on field data from real visitors when there is enough traffic.
Get your store's speed priorities
Book a short call and share your store address. We look at your apps, theme and product pages and tell you which fixes would make the biggest difference.
Book a free 15-minute call