How to speed up a Shopify store: a practical checklist

To speed up a Shopify store, fix things in the order they actually cost you: apps first, images second, theme code third. Speed optimization is the work of cutting how long a browser takes to show a usable page. Most guides hand you twenty tips of equal weight. In reality two or three changes do almost all the work, and the rest is rounding error.

We wrote the why-it-happens version of this already. This is the how-to-fix-it companion: the actual checklist, in priority order, so you spend your time where it moves the number.

Step 1: Measure before you touch anything

A benchmark is the load-time number you improve against, and skipping it means you can’t tell a real fix from a placebo. Run your homepage and one product page through PageSpeed Insights and write down the mobile score and the largest-contentful-paint time. Mobile, not desktop. That’s where most of your traffic and nearly all of your slowness lives.

Do this twice: once now, once after each change. If a “fix” doesn’t move the number, undo it.

Step 2: Audit your apps first

App bloat is the scripts third-party apps inject on every page, and it’s almost always the single biggest drag on a Shopify store. We measured this directly: in our audit of 8 real DTC stores, the heaviest homepage carried 96 script tags, most of them apps. Open your installed apps and be honest about each one.

Uninstalling one heavy, unused app usually beats a week of image tweaking. Start there.

Step 3: Fix your images

Images are typically the largest files a page loads, so oversized ones are pure, avoidable weight. Serve them in a modern format like WebP, size them to the space they actually fill, and lazy-load anything below the fold. A 4000px hero image scaled down in the browser still downloads all 4000 pixels. That’s wasted bandwidth on every single visit.

Step 4: Trim the theme, don’t rebuild it yet

Theme code is the Liquid, CSS, and JavaScript your template ships, and it’s the last place to look, not the first. Remove unused apps’ leftover code snippets, cut sliders and carousels you don’t need, and defer non-critical scripts. This matters, but it’s a smaller lever than apps or images, so don’t start here. If your theme is genuinely old and heavy, that’s a redesign conversation, not a quick fix.

Why speed is a conversion problem, not a vanity metric

Load time is how long a visitor waits, and every second of it quietly costs you sales. A slow page loses visitors before they see a single product, which is why speed sits upstream of everything in our conversion rate guide. You’re not chasing a green score to feel good. You’re stopping paid clicks from bouncing before they convert.

FAQ

What slows a Shopify store down most?

Third-party apps, almost always. Each one adds scripts to every page. Oversized images come second; theme code is usually a distant third.

How do I check my Shopify speed?

Run your homepage and a product page through PageSpeed Insights on mobile. Note the score and load time, then re-check after each change you make.

Will removing apps really make it faster?

Usually yes, and it’s the biggest single lever. One heavy, unused app often costs more speed than every image on the page combined.

Is a green PageSpeed score necessary?

No. Chase real load time and mobile experience, not a perfect score. Past “good enough,” extra points rarely change what visitors feel.

Should I switch themes to go faster?

Only if yours is genuinely old and heavy. For most stores, cutting apps and fixing images beats a theme swap and costs far less.

Want to know exactly what’s slowing your store, in priority order? Send us the URL and we’ll tell you the top three fixes. Usually a reply within the hour.