Free AI Speed Diagnosis:
See What's Slowing Your Shopify Store
Test your store's speed in 30 seconds. See how you compare to other Shopify stores — and exactly what's costing you sales.
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
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Results for
Largest Contentful Paint
Based on $50k/mo avg · Google/Deloitte data
Thunder fixes 0 of 0 issues instantly
Potential With Thunder
Free plan · No credit card · 1-click install
Issues Found
Why Is Your Shopify Store So Slow?
You've optimized images. Minified CSS. Picked a fast theme. But your PageSpeed score is still stuck in the 30s. Here's the dirty secret most speed apps won't tell you:
Loading... 5.2s
Loaded in 1.4s
of Shopify speed issues come from third-party app scripts
average load time increase from installing just 5 apps
conversion rate drop for every 1 second of added load time
What Thunder Does Differently
Not just another image optimizer. Thunder goes after the real speed killers.
See Exactly What's Slowing You Down
Thunder scans your store and shows you which installed apps are dragging your speed down — then fixes them automatically. No other speed app does this.
Smart Script Optimization
Automatically defers, lazy loads, and prioritizes JavaScript execution. Reduce render-blocking resources without breaking functionality.
Core Web Vitals Monitoring
Real-time LCP, FID, and CLS tracking built into your Shopify dashboard. Know exactly where you stand and what to fix next.
Advanced Lazy Loading
Intelligent lazy loading for images, videos, and iframes. Loads what visitors need when they need it — not everything at once.
One-Click Optimization
No technical knowledge required. Install Thunder, click optimize, and watch your speed score climb. Most stores see improvements in under 60 seconds.
Safe & Reversible
Thunder never modifies your theme code. All optimizations are applied at the network level and can be turned off instantly. Zero risk.
Rank Higher on Google
Page speed is an official Google ranking factor. Stores that pass Core Web Vitals rank higher in search results. Thunder helps you pass all three metrics — so you get more free organic traffic.
How It Works
Three steps. Under five minutes. No developer needed.
Install Thunder
Add Thunder from the Shopify App Store. Free plan available — no credit card required. Works with every Shopify theme.
Thunder Scans Your Store
Thunder analyzes every script running on your store, identifies the worst offenders, and builds an optimization plan tailored to your specific setup.
Watch Your Score Climb
One-click apply. Thunder optimizes script loading order, defers non-critical resources, and starts monitoring your Core Web Vitals. Most stores see a 20-40 point PageSpeed improvement.
Trusted by Shopify Store Owners
“Our PageSpeed score went from 34 to 78 after installing Thunder. The third-party app scanner was a game-changer — we had no idea Klaviyo was adding 1.8s to our load time.”
“Tried Booster and Hyperspeed before Thunder. Neither fixed our actual problem — too many app scripts. Thunder identified the issue in seconds and fixed it automatically.”
“Finally an app that tells you WHY your store is slow, not just tries to slap a bandaid on it. Core Web Vitals monitoring in the dashboard is incredibly useful.”
Proven by Data
0.1 seconds faster = 8.4% more conversions
Google and Deloitte proved it across 37 brands and 30 million sessions. Source →
32%
more bounce rate
when load time goes from 1s → 3s
Google/SOASTA, 2017
90%
more bounce rate
when load time goes from 1s → 5s
Google/SOASTA, 2017
1%
sales lost per 100ms
of added latency at Amazon
Amazon, internal study
BBC found they lose
10% of users
for every additional second of load time.
Your store is losing money every second it loads slowly. Thunder finds and fixes the bottlenecks.
Speed = Higher Google Rankings
A faster Shopify store doesn't just convert better — it ranks higher on Google. Core Web Vitals became an official Google ranking factor in June 2021. Stores that pass CWV get a measurable boost in search visibility. Google's announcement →
June 2021
Core Web Vitals became a Google ranking factor
Google confirmed: page experience signals directly affect search rankings
Top 10
Pages passing CWV are more likely to appear in Google's top 10
Speed is no longer optional if you want organic traffic
The bottom line:
Slow stores lose rankings. Fast stores win them.
Thunder helps your Shopify store pass Core Web Vitals — Google's official speed benchmark for search rankings.
A Message From
the Founder
"I've spent years building and optimizing Shopify stores for 8 and 9-figure brands. The same problem came up every single time: the store was fast until we installed the apps the business needed to run.
Review widgets. Email popups. Analytics. Chat. Loyalty programs. Upsells. Every app added another JavaScript payload, another render-blocking script, another 200-500ms to the load time. A store that scored 90 on PageSpeed would drop to 40 after installing 15 essential apps.
The worst part? There was no way to fix it without breaking things. You could try manually deferring scripts, but one wrong move and your reviews disappear, your analytics stop tracking, or your checkout breaks. Most merchants just accepted the slowdown.
I couldn't. I watched stores lose thousands in revenue every month because their apps — the tools they needed — were silently killing their speed. So I built a solution for my clients: a tool that scans every installed app, measures its exact speed impact, and intelligently optimizes how scripts load — without breaking a single feature.
It worked. Stores saw 20-40 point PageSpeed improvements. Conversions went up. Google rankings improved. My clients asked why this wasn't available to everyone.
So I made it available to everyone.
Thunder isn't another generic speed optimizer that applies the same lazy loading every other app does. It's the only tool that shows you exactly which apps are slowing your store and fixes the problem at the source. Because I built it solving real problems for real stores — not in a vacuum."
Stop Losing Sales & Rankings to a Slow Store
Every second of load time costs you conversions and Google rankings. Speed is an official ranking factor — Thunder helps you pass Core Web Vitals so you convert better and rank higher.
Install Thunder Free →Free plan available. No credit card required. Installs in under 60 seconds.