Comparison · Updated February 2026
Thunder vs Booster Page Speed Optimizer
An honest, detailed comparison of two popular Shopify speed optimizers. We'll cover features, pricing, strengths, and weaknesses — so you can pick the right tool for your store.
8.4%
more conversions
per 0.1s faster
90%
more bounce
at 5s load time
+53%
revenue/visitor
after CWV fixes
Every millisecond counts. Stores that load 0.1s faster see 8.4% more conversions (Google/Deloitte, 37 brands). Speed is also a Google ranking factor — faster stores get more organic traffic. Choose the right speed optimizer.
⚡ Quick Verdict
Choose Thunder if your main speed issue is third-party app bloat. Thunder's script scanner identifies exactly which apps are slowing you down and fixes them automatically — which helps improve your Google search rankings by passing Core Web Vitals. A capability Booster doesn't offer. Choose Booster if you want a well-established app with a larger community, browser caching, and DNS prefetching features. Both have free plans, so you can test each on your own store.
Overview
⚡ Thunder Page Speed Optimizer
- • Rating: 4.6★ (59 reviews)
- • Focus: Maximum speed improvement with smart diagnostics & Core Web Vitals monitoring
- • Pricing: Free plan, paid plans from $9/mo
- • Built for Shopify: Not yet
- • Unique feature: Per-app speed diagnostics — shows exactly what's slowing your store
🚀 Booster Page Speed Optimizer
- • Rating: 4.7★ (364 reviews)
- • Focus: Browser caching, lazy loading, preloading
- • Pricing: Free
- • Built for Shopify: No
- • Unique feature: DNS prefetching, browser caching
Feature Comparison
| Feature | Thunder | Booster |
|---|---|---|
| Third-party app script scanner | ✓ | ✗ |
| Smart script deferral | ✓ | ✓ |
| Lazy loading (images) | ✓ | ✓ |
| Lazy loading (videos/iframes) | ✓ | ~ |
| Core Web Vitals monitoring | ✓ | ✗ |
| Browser caching | ✗ | ✓ |
| DNS prefetching | ✗ | ✓ |
| Preconnect hints | ✓ | ✓ |
| Critical CSS optimization | ~ | ✗ |
| One-click optimization | ✓ | ✓ |
| No theme code changes | ✓ | ✓ |
| Free plan | ✓ | ✓ |
| Real-time speed dashboard | ✓ | ✗ |
| Per-app speed impact reports | ✓ | ✗ |
Detailed Breakdown
Third-Party Script Handling
This is where Thunder and Booster diverge the most. The average Shopify store runs 15-25 third-party app scripts — review widgets, email popups, analytics trackers, chat widgets — and these are responsible for the majority of speed issues.
Thunder scans every installed app, measures each script's impact on page load time, and gives you a report showing exactly which apps are the worst offenders. It then optimizes how those scripts load — deferring non-essential ones, reducing their blocking time, and prioritizing critical functionality. This is Thunder's core differentiator.
Booster applies general-purpose optimizations — lazy loading, preloading, caching — but doesn't specifically analyze or target third-party app scripts. If your speed problem is caused by a particularly heavy app (like some review or loyalty apps), Booster won't identify or fix it.
Core Web Vitals
Thunder includes built-in Core Web Vitals monitoring (LCP, FID/INP, CLS) directly in your Shopify dashboard. You can track your scores over time and see how optimizations affect real user metrics. This is genuinely useful for understanding your store's performance, not just a vanity PageSpeed score.
Booster doesn't offer Core Web Vitals monitoring. You'd need to check Google PageSpeed Insights or Google Search Console separately, which most merchants don't do regularly.
Caching & Network Optimization
This is where Booster has the edge. Booster offers browser caching controls and DNS prefetching — techniques that speed up repeat visits and reduce DNS lookup times. Thunder currently focuses more on script-level optimization and doesn't include dedicated caching features.
That said, Shopify's CDN already handles most caching effectively, so the practical impact of additional browser caching varies by store.
Pricing Comparison
⚡ Thunder Pricing
- Free Plan$0/mo
- Basic script optimization, app scanner (limited)
- Pro Plan$9/mo
- Full optimization, CWV monitoring, priority support
🚀 Booster Pricing
- Free$0/mo
- All features included — Booster is completely free
Booster wins on pricing — it's completely free. Thunder's free plan covers basics, but you'll need the $9/mo Pro plan for full Core Web Vitals monitoring and advanced optimizations.
Pros & Cons
⚡ Thunder
✓ Pros
- • Unique third-party app script scanner
- • Built-in Core Web Vitals monitoring
- • Per-app speed impact reports
- • Targets the #1 cause of slow Shopify stores
- • Clean, modern interface
✗ Cons
- • Smaller review base (59 vs 364 reviews)
- • No browser caching features
- • Full features require $9/mo plan
- • Not yet "Built for Shopify" certified
🚀 Booster
✓ Pros
- • Completely free
- • Larger, more established user base
- • Browser caching and DNS prefetching
- • Simple, set-and-forget setup
✗ Cons
- • No third-party script analysis
- • No Core Web Vitals monitoring
- • Doesn't identify which apps slow your store
- • Less granular optimization controls
- • Not "Built for Shopify" certified
Who Should Pick Which?
Pick Thunder if you…
- ✓ Have many installed apps (10+) and suspect they're slowing your store
- ✓ Want to know exactly which apps affect your speed
- ✓ Need Core Web Vitals monitoring in your dashboard
- ✓ Have already tried basic optimizations and need deeper fixes
- ✓ Are willing to invest $9/mo for comprehensive optimization
Pick Booster if you…
- ✓ Want a completely free solution
- ✓ Need basic lazy loading and preloading
- ✓ Don't have many third-party apps installed
- ✓ Want browser caching and DNS prefetching
- ✓ Prefer a more established app with a larger community
Frequently Asked Questions
Is Thunder better than Booster Page Speed Optimizer?
It depends on your needs. Thunder is better at fixing third-party app script bloat and offers Core Web Vitals monitoring. Booster is more established with a larger review base and provides browser caching and DNS prefetching. Thunder is the better choice if slow apps are your main speed issue.
Can I use Thunder and Booster together?
We don't recommend running two speed optimizers simultaneously. They can conflict with each other's optimizations, causing unexpected behavior. Choose one and test your results.
Which app has a better free plan?
Both offer free plans. Booster's free plan includes basic speed optimization and lazy loading. Thunder's free plan includes third-party app scanning and basic script optimization. Both are useful for getting started.
Do these apps work with all Shopify themes?
Both Thunder and Booster work with all Shopify themes. Neither modifies your theme code directly — they apply optimizations at the script/network level.
Try Thunder Free
See which apps are slowing your store. Install Thunder and get your speed report in under 60 seconds.
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