LCP
Largest Contentful Paint
4.5s
Poor
Good: < 2.5s
Measures how long it takes for the main content to appear on screen
Remove Unused JavaScript Code
How to optimize cwt.dev.bb10a50c1ba6.herokuapp.com
Remove Unused JavaScript Code
High Impact+15 points estimated
Why It Matters
Unused JavaScript is wasting 366 KiB and delaying LCP by 1 second.
How to Fix
Configure Next.js tree shaking by using named imports instead of default imports. Analyze bundle with @next/bundle-analyzer to identify unused code. Split large chunks using dynamic imports for components below the fold. Remove unused Stripe.js code if not needed on all pages.
0Needs Improvement
What This Score Means
A score of 77 falls in the "Needs Improvement" range (50-89). While it is better than poor (0-49), you should aim for 90+ to provide an optimal user experience and maximize SEO benefits.
This site is slower than approximately 35% of similar sites. The main issues affecting performance are image optimization, JavaScript execution time, and layout stability.
Addressing these issues could improve your conversion rate by 15-20% and boost your search engine rankings.
Core Web Vitals Analysis
INP
Interaction to Next Paint
159ms
Good
Good: < 200ms
Measures how quickly the page responds to user interactions
CLS
Cumulative Layout Shift
0.02
Good
Good: < 0.1
Measures visual stability - how much content shifts during page load
AI Performance Analysis
This Next.js site has moderate performance issues with a score of 77/100. The biggest problem is excessive unused JavaScript code, particularly from a large JavaScript file and Stripe integration, which wastes 366 KiB and delays page interactivity by over 1 second. The site also suffers from render-blocking CSS files that could save 840ms if properly optimized, and oversized images that are larger than their display dimensions. Removing unused JavaScript, optimizing CSS delivery, and properly sizing images could significantly improve the user experience and boost the performance score by 15-20 points.
Other Optimization Recommendations
Optimize Hero Image Sizing
High Impact+12 points estimatedWhy It Matters:
The LCP hero image is 46 KiB larger than needed and delays LCP by 300ms.
How to Fix:
Update Next.js Image component to use proper responsive sizes prop based on viewport breakpoints. Set sizes='(max-width: 640px) 100vw, 637px' for the hero image. Add fetchpriority='high' to the LCP image element to prioritize its loading.
Eliminate Render Blocking CSS
Medium Impact+8 points estimatedWhy It Matters:
CSS files are blocking initial render and delaying FCP by 850ms.
How to Fix:
Configure Next.js to inline critical CSS for above-the-fold content using @next/bundle-analyzer. Move non-critical CSS to load asynchronously using next/dynamic with ssr: false. Combine smaller CSS chunks to reduce the number of blocking requests.
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Related Performance Analyses
More Next.js Speed Tests
Next.js Performance Resources
Eliminate Render Blocking CSS
CSS files are blocking initial render and delaying FCP by 850ms.
Optimize Hero Image Sizing
The LCP hero image is 46 KiB larger than needed and delays LCP by 300ms.
Add Preconnect for External Origins
Missing preconnect hints waste 300ms establishing connections to external domains.
Remove Unused JavaScript Code
407 KiB of unused JavaScript is delaying LCP by 2.1 seconds and blocking user interactions.