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Shopify Speed Leak Checker

Paste your store URL. We run Google PageSpeed Insights, pull your Largest Contentful Paint, and convert the gap to recoverable monthly revenue at your traffic. No sign-up, no email gate, no upsell pop-up. Just the number.

[ Step 1 ]

Paste your store

Optional — fine-tune the revenue math
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Defaults reflect the median Shopify store. Replace with your real numbers for an honest leak figure.

Why Shopify page speed actually moves revenue

The most cited number in ecommerce speed research is also the most important: a one-second delay in mobile page load can drop conversion rate by up to seven percent. Shopify references the same cluster of studies in their own commerce trends reports, because it's true at scale across categories. Speed isn't a hygiene metric — it's a revenue lever that compounds with every other lever you pull.

Most Shopify operators don't fix their speed because the data feels abstract. "LCP 4.2 seconds" doesn't motivate anyone. "Your speed is leaking $1,840 a month" does.

What's a good LCP for a Shopify store?

Five fixes that move LCP the most on Shopify

1. Audit and uninstall app bloat

Every Shopify app you install adds JavaScript to every page load — even pages where the app does nothing. Uninstall anything you haven't opened in 60 days. This is usually the single biggest LCP win you can ship in an hour.

2. Compress your hero image and serve modern formats

The first image above the fold is usually your LCP element. If it's a 2MB PNG, that's your problem. Convert to WebP, target under 200KB for the hero, set explicit width and height to prevent layout shift.

3. Lazy-load everything below the fold

Add loading="lazy" to every image that isn't above the fold. Most Shopify themes do this by default now — but check yours. If your theme is older than 2022, this might be your easiest 500ms win.

4. Defer non-critical third-party scripts

Klaviyo, reviews apps, chat widgets, GTM tags — these are the silent LCP killers. Move what you can to defer or load it after first interaction. The Shopify Web Pixel API is the right place to put marketing tags now.

5. Pick a fast theme and stop fighting it

Some themes are simply faster than others. Dawn (Shopify's own) is one of the fastest free themes in the ecosystem. If your theme has 40+ sections you don't use, sometimes the right answer is just to swap themes — not optimize the one you have.

Once you've shipped these five, run this checker again. The drop in your monthly leak figure is usually the most satisfying number an operator sees all month. For the other seven leaks, run the full Shopify audit.

Speed Checker FAQ

Five honest answers about what this measures and what to do with the number.

How does the Shopify Speed Leak Checker work?

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Paste your store URL and we run Google PageSpeed Insights against it on a simulated mobile device. We pull your Largest Contentful Paint (LCP), the score Google itself uses to grade real-world Core Web Vitals, and we convert the gap between your LCP and the 2.5-second "good" threshold into recoverable monthly revenue — using your own visitors, AOV, and conversion rate. The math is conservative: 7% conversion lift per second of LCP recovered, capped at 30%, based on the Akamai and Portent studies that Shopify itself references.

Why does Shopify speed actually matter for revenue?

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Shopify's own commerce data shows mobile conversion rates fall sharply once page load crosses three seconds. Google's research is even more direct: probability of bounce climbs 32% as page load goes from one to three seconds, and 90% from one to five. For most Shopify stores, mobile is 70%+ of traffic — so a slow LCP isn't a technical problem, it's a revenue problem. Plugging the speed leak is usually one of the highest-ROI fixes available, because it lifts every other conversion lever at once.

Is this just Google PageSpeed Insights wrapped in a fancy UI?

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The data comes from PageSpeed Insights (it's the most authoritative free source), but the leverage is the math layer on top. PSI gives you a score and a list of audits. The Speed Leak Checker tells you what those numbers cost you in dollars per month at your traffic level — which is the only framing that gets a busy operator to actually fix it. We also surface only the top opportunities ranked by estimated savings, instead of dumping the full Lighthouse audit list.

Will this work on a password-protected dev store?

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No — PageSpeed Insights renders your storefront the same way a customer would, so it can't get past Shopify's storefront password gate. Remove the password (or run it on a public clone) and try again. If you're pre-launch, run it on a competitor's store instead — it's a useful benchmark to know what you're shipping into.

What's the next step once I have my speed leak number?

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Run the full LeakAudit on the same store — it'll find the other 27 leaks, not just the speed one. Speed is rarely the whole story: most stores have stacked leaks across product page hierarchy, trust signals, mobile checkout friction, and app bloat. The Speed Leak Checker is the appetizer; the full audit is the meal. Run the free Shopify audit →
More answers in the full FAQ.

Speed is the appetizer.
The audit is the meal.

Find the other seven leaks dragging down your store — across product page, trust, mobile, copy, and more.

Run My Free Shopify Audit →
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