Free Speed Test for Your Shopify Store
See exactly what's slowing your store and how to fix it. Powered by Google PageSpeed Insights.
Free · No signup · Results in ~30 seconds · Powered by Google PageSpeed Insights
+8.4%
conversions per 0.1s faster
2.5×
more sales for 1s vs 5s load
32%
more bounce at 3s load time
-7%
conversions per 1s slower
Sources: Google/Deloitte 2020, Google/SOASTA 2017
Did you know?
A 1-second delay in page load reduces conversions by 7%.
Analysis Failed
Results for
Largest Contentful Paint
Core Web Vitals are an official Google ranking signal.
Source: Google/Deloitte 2020
Source: Google/SOASTA 2017
Core Web Vitals
Issues Found
What You Can Do
Thunder can automatically fix 0 of 0 issues found above.
Most stores see a 20–40 point improvement. Free plan available.
Get automated optimization →Free plan · No credit card · 1-click install on Shopify
Why Test Your Shopify Store Speed?
Page speed isn't just a technical metric — it directly impacts your revenue. Google has confirmed that page speed is a ranking factor, and research consistently shows that faster-loading stores convert significantly better than slow ones.
Speed = Revenue
per 0.1s faster
Studies from Google and Deloitte show that even a 0.1-second improvement in load time can increase conversions by 8%. On the flip side, if your store takes more than 3 seconds to load, over 50% of mobile visitors will leave before seeing a single product.
50%
of mobile visitors bounce at 3+ second load times
Sources: Google/Deloitte 2020, Google/SOASTA 2017
Speed = Google Rankings
Google ranking signal
Google uses Core Web Vitals as a ranking factor for search results. Our tool uses Google's PageSpeed Insights API to measure the same metrics Google uses for search rankings:
- Largest Contentful Paint (LCP) — How quickly your main content becomes visible. Under 2.5s is "good."
- First Contentful Paint (FCP) — When the first element renders. Under 1.8s is ideal.
- Cumulative Layout Shift (CLS) — How much your page shifts while loading. Under 0.1 is the target.
- Total Blocking Time (TBT) — How long JavaScript blocks interaction. Under 200ms is good.
Source: Google Search Central 2021
The Real Cost of a Slow Store
on an average Shopify store
For Shopify merchants, speed is especially critical. The average Shopify store loads dozens of third-party scripts from apps like Klaviyo, Judge.me, Loox, and page builders. Each script adds weight to your page, competing for bandwidth and processing power on your customers' devices.
Common culprits: Klaviyo email popups, Judge.me reviews, Loox photo reviews, page builders, chat widgets, upsell apps — each adding 50-500KB of JavaScript.
What Thunder Does Differently
PageSpeed improvement
After running the test, you'll see specific recommendations. The most impactful changes for Shopify stores typically involve optimizing how third-party scripts load. You can do this manually by editing your theme's Liquid templates, or use a tool like Thunder to automate it.
Thunder defers non-critical JavaScript, reduces render-blocking resources, and intelligently manages script execution — automatically, with one click.
Free plan available · No code changes required