Scanned on June 13, 2026
Sorted by score impact — each fix moves your overall grade up.
Weight: 25% · 5 passed · 7 warnings · 7 failed
Why it matters: FCP over 3s means users stare at a blank screen for 3+ seconds. 53% of mobile users abandon sites that take over 3 seconds to show content.
How to fix: Critical: enable full-page caching, eliminate render-blocking resources, preload critical CSS, defer all non-essential JS, and compress images.
What we found: 8.46s (good: <1.8s)
Why it matters: FCP over 3s means users stare at a blank screen for 3+ seconds. 53% of mobile users abandon sites that take over 3 seconds to show content.
Why it matters: LCP >4s fails Core Web Vitals — Google actively demotes these pages. Each 100ms improvement in LCP correlates with 1.7% higher conversion rate (Vodafone study).
How to fix: Urgent: your largest content element loads too slowly. 1) Preload hero image, 2) Convert to WebP/AVIF, 3) Serve from CDN, 4) Remove render-blocking JS before it, 5) Consider lazy loading all other images.
What we found: 16.14s (good: <2.5s) — Core Web Vital FAILING
Why it matters: LCP >4s fails Core Web Vitals — Google actively demotes these pages. Each 100ms improvement in LCP correlates with 1.7% higher conversion rate (Vodafone study).
Why it matters: TBT over 600ms means your page is unresponsive for over half a second. Users who can't interact within 100ms perceive the site as broken. This kills conversions.
How to fix: Critical: audit all JavaScript. 1) Remove unused plugins/modules, 2) Defer analytics and chat widgets, 3) Code-split large bundles, 4) Move heavy computation to web workers.
What we found: 2316ms (good: <200ms)
Why it matters: TBT over 600ms means your page is unresponsive for over half a second. Users who can't interact within 100ms perceive the site as broken. This kills conversions.
Why it matters: Speed Index over 5.8s means users watch a near-blank page for almost 6 seconds. At this speed, you're losing 40%+ of potential customers to competitors.
How to fix: Your page loads very slowly visually. Prioritize critical rendering path: inline critical CSS, defer non-essential JS, preload hero image, and use a CDN.
What we found: 20.14s (good: <3.4s)
Why it matters: Speed Index over 5.8s means users watch a near-blank page for almost 6 seconds. At this speed, you're losing 40%+ of potential customers to competitors.
Why it matters: Pages over 3 MB take 12+ seconds on 3G. The average e-commerce page is 2.2 MB — you're well above that. Amazon found every 100ms of latency costs 1% of sales.
How to fix: Critical: your page is over 3 MB. 1) Convert all images to WebP/AVIF, 2) Lazy load everything below the fold, 3) Remove unused plugins, 4) Combine and minify CSS/JS, 5) Enable brotli compression.
What we found: 12.5 MB, 290 requests — too heavy!
Why it matters: Pages over 3 MB take 12+ seconds on 3G. The average e-commerce page is 2.2 MB — you're well above that. Amazon found every 100ms of latency costs 1% of sales.
Why it matters: Over 200 KB of unused code significantly slows parsing and execution. This is one of the easiest performance wins — removing dead code requires no trade-offs.
How to fix: You're loading 1967 KB of code that isn't used on this page. 1) Audit plugins and remove unused ones, 2) Use code-splitting for page-specific JS, 3) Run PurgeCSS on your stylesheets.
What we found: 1967 KB wasted on unused code!
Why it matters: Over 200 KB of unused code significantly slows parsing and execution. This is one of the easiest performance wins — removing dead code requires no trade-offs.
Note: This check uses heuristic detection and may produce false positives. Manual verification recommended.
Why it matters: Each CSS file blocks rendering. With 11 files, the browser must download all of them before painting anything. This can add 1-2+ seconds on mobile networks.
How to fix: Bundle your CSS files into 1-3 files maximum. Use a build tool (Webpack, Vite, Gulp) to concatenate and minify. Critical CSS should be inlined, the rest deferred.
What we found: 11 CSS files — too many!
Why it matters: Each CSS file blocks rendering. With 11 files, the browser must download all of them before painting anything. This can add 1-2+ seconds on mobile networks.
Why it matters: Without lazy loading, ALL images download on page load — even those never scrolled to. On a product page with 20 images, lazy loading can save 80%+ of initial download.
How to fix: Add loading='lazy' to all images below the fold. Keep the hero/LCP image eager-loaded. Native lazy loading is supported by all modern browsers.
What we found: 376 images without lazy loading
Why it matters: Without lazy loading, ALL images download on page load — even those never scrolled to. On a product page with 20 images, lazy loading can save 80%+ of initial download.
Why it matters: Without cache headers, browsers use heuristic caching which is unpredictable. Explicit caching can eliminate 60%+ of requests for repeat visitors.
How to fix: Add Cache-Control headers: 'max-age=31536000, immutable' for versioned static assets, 'max-age=0, must-revalidate' for HTML.
Why it matters: Without cache headers, browsers use heuristic caching which is unpredictable. Explicit caching can eliminate 60%+ of requests for repeat visitors.
Why it matters: Synchronous scripts block HTML parsing — the browser stops rendering until each script downloads and executes. Async/defer allows parallel downloading without blocking.
How to fix: Add 'defer' to scripts that don't need to run immediately, 'async' for independent scripts. Use type='module' for modern ES modules. Only critical inline scripts should be synchronous.
What we found: Only 60% of 5 scripts use async/defer
Why it matters: Synchronous scripts block HTML parsing — the browser stops rendering until each script downloads and executes. Async/defer allows parallel downloading without blocking.
Why it matters: Fonts are discovered late in the render pipeline (after CSS is parsed). Preloading tells the browser to download them immediately, reducing Flash of Invisible Text (FOIT) by 200-500ms.
How to fix: Preload your primary font: <link rel='preload' href='/fonts/main.woff2' as='font' type='font/woff2' crossorigin>. For Google Fonts: preconnect to fonts.gstatic.com.
What we found: Custom fonts detected without preload hints
Why it matters: Fonts are discovered late in the render pipeline (after CSS is parsed). Preloading tells the browser to download them immediately, reducing Flash of Invisible Text (FOIT) by 200-500ms.
Why it matters: Render-blocking CSS delays first paint. Inlining critical CSS eliminates the render-blocking round trip — the biggest FCP improvement for CSS-heavy sites.
How to fix: Extract critical above-the-fold CSS and inline it in <head>. Load remaining CSS asynchronously: <link rel='preload' href='styles.css' as='style' onload='this.rel="stylesheet"'>.
What we found: 11 CSS files without critical CSS extraction
Why it matters: Render-blocking CSS delays first paint. Inlining critical CSS eliminates the render-blocking round trip — the biggest FCP improvement for CSS-heavy sites.
Why it matters: Third-party connections require DNS lookup, TCP handshake, and TLS negotiation. Preconnect performs these in parallel with HTML parsing, saving 100-300ms per origin.
How to fix: Add <link rel='preconnect'> for key third-party domains: www.googletagmanager.com, www.google.com, code.jquery.com. Preconnect saves 100-300ms per domain by starting DNS+TCP+TLS early.
What we found: 4 external domains without preconnect
Why it matters: Third-party connections require DNS lookup, TCP handshake, and TLS negotiation. Preconnect performs these in parallel with HTML parsing, saving 100-300ms per origin.
Why it matters: Large inline scripts cannot be cached separately — they're re-downloaded with every page load. Moving them to external files with defer enables HTTP caching and parallel downloads.
How to fix: Move large inline scripts to external files. Inline JS over 100 KB inflates HTML, prevents caching, and blocks the parser. External files can be cached, compressed, and deferred.
What we found: 2599 KB of inline JavaScript
Why it matters: Large inline scripts cannot be cached separately — they're re-downloaded with every page load. Moving them to external files with defer enables HTTP caching and parallel downloads.
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| Kategória | Skóre | Váha | Chyby | Upozornenia | OK |
|---|---|---|---|---|---|
| Performance | 36/100 | 25% | 7 | 7 | 5 |
| SEO | 83/100 | 20% | 1 | 4 | 12 |
| Security | 37/100 | 15% | 4 | 8 | 3 |
| Mobile | 41/100 | 10% | 3 | 10 | 5 |
| AI Readiness | 48/100 | 10% | 4 | 18 | 4 |
| GDPR | 61/100 | 10% | 2 | 5 | 6 |
| Vulnerability | 64/100 | 10% | 4 | 5 | 10 |
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https://score.zulien.sk/r/farlesk.sk