LCP
Largest Contentful Paint
3.9s
Needs Improvement
Good: < 2.5s
Measures how long it takes for the main content to appear on screen
Remove Unused JavaScript Code
How to optimize blacklabs.it
Generic SiteScore: 87/100Analyzed February 2026
Remove Unused JavaScript Code
High Impact+8 points estimated
Why It Matters
102 KiB of unused JavaScript is delaying LCP by 400ms and blocking critical page rendering.
How to Fix
Analyze analytics script to remove 83KB of unused code or defer non-essential features. Tree-shake the Astro page bundle to eliminate 21KB of unused functions. Use dynamic imports to load JavaScript modules only when needed.
0Needs Improvement
What This Score Means
A score of 87 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
75ms
Good
Good: < 200ms
Measures how quickly the page responds to user interactions
CLS
Cumulative Layout Shift
0.00
Good
Good: < 0.1
Measures visual stability - how much content shifts during page load
AI Performance Analysis
This website has good performance with a score of 87/100, but there's still room for improvement. The biggest issue is slow Largest Contentful Paint at 3.9 seconds, primarily caused by unused JavaScript that's wasting 102 KiB of data and delaying page rendering by 390 milliseconds. The site is loading too much unnecessary JavaScript code, particularly from analytics scripts where over half the code isn't being used. Removing unused JavaScript and implementing better caching for third-party scripts could significantly speed up the initial page load and improve the user experience.
Other Optimization Recommendations
Add Preconnect to Sentry Domain
Medium Impact+4 points estimatedWhy It Matters:
DNS lookup to Sentry is adding 70ms delay to LCP and creating network dependency bottleneck.
How to Fix:
Add <link rel='preconnect' href='https://o4508751822127104.ingest.de.sentry.io'> to your HTML head. Consider deferring Sentry initialization until after page load. Move error tracking to load after critical content is rendered.
Implement Long-term Asset Caching
Medium Impact+3 points estimatedWhy It Matters:
Poor cache policies waste 14KB on repeat visits and slow down returning user experience.
How to Fix:
Set cache-control headers to 1 year for static Astro assets using your CDN settings. Configure Cloudflare to cache Zaraz scripts for longer periods. Add versioning to JavaScript bundles to enable aggressive caching.
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Related Performance Analyses
More Generic Speed Tests
Generic Performance Resources
Remove Unused JavaScript Code
Google Tag Manager scripts contain 139KB of unused code, slowing LCP by 600ms and wasting processing time.
Optimize Video File Caching
17MB of video content has zero cache lifetime, forcing full re-downloads on every visit and wasting 69MB of bandwidth.
Defer Render-Blocking JavaScript
JavaScript files are blocking initial page render, delaying FCP by 750ms and preventing users from seeing content.
Remove Unused CSS and JavaScript
136KB of unused JavaScript and 63KB of unused CSS waste bandwidth and slow down page parsing.
Frequently Asked Questions
Keep Your Site Fast After Optimization
Once your site is optimized, maintain that speed. Use DeployHQ for zero-downtime, automated deployments—so performance fixes and updates go live safely every time, without breaking your site.
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