Measure your site's Core Web Vitals (LCP, INP, CLS), page speed, and performance score. Free, instant results — every scan builds your documented compliance record.
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Google uses these metrics as ranking signals. All three must be "Good" to pass the Core Web Vitals assessment.
Measures how quickly the largest content element (image, heading, or text block) loads. The most important user-perceived loading metric.
Measures the delay from user interaction (click, tap, keypress) to the next visual update. Replaced FID as a Core Web Vital in 2024.
Measures unexpected layout shifts during page load — buttons and links jumping around as images and fonts load. Directly impacts user trust.
Time from navigation to first text or image rendered. Indicates when the page starts appearing to the user.
Time from request to first byte of response. Reflects server response time, CDN efficiency, and hosting quality.
Total time the main thread was blocked between FCP and TTI. Indicates JavaScript execution overhead that delays interactivity.
Content Delivery Networks (CDNs) serve assets from edge locations close to the user. Sites on Cloudflare or similar CDNs typically cut TTFB by 60–80% for global visitors.
Images are the #1 cause of slow LCP. Use modern formats (WebP, AVIF), compress to 80–85% quality, set explicit width/height attributes, and lazy-load off-screen images.
Large JS bundles are the top cause of high TBT and INP. Remove unused code, split bundles, defer non-critical scripts, and avoid render-blocking third-party scripts.
Prevent CLS by always setting explicit width and height on images and video embeds. Reserve space for ad slots. Avoid inserting content above existing content.
Use for critical fonts, hero images, and above-the-fold CSS. This tells the browser to fetch high-priority resources early in the loading process.
Set long cache-control headers (1 year) for versioned static assets. Use service workers for offline caching. CDN edge caching for HTML responses reduces TTFB dramatically.
Performance regressions happen silently. A slow plugin update, a large image added to a CMS post — and your Core Web Vitals drop. PageGuard alerts you the moment your performance score falls, and every scan is automatically saved to your performance compliance record.
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Core Web Vitals are Google's three key metrics for user experience: LCP (loading speed), INP (interactivity), and CLS (visual stability). Google uses them as ranking signals — sites with all three in the "Good" range receive a ranking boost.
Google's Page Experience ranking signal includes Core Web Vitals. Sites passing all three Core Web Vitals thresholds get a ranking boost. Beyond SEO, faster sites convert better — a 1-second improvement increases e-commerce conversions by up to 7%.
Lighthouse scores 90–100 are "Good", 50–89 are "Needs Improvement", and below 50 are "Poor". For Core Web Vitals: LCP <2.5s, INP <200ms, CLS <0.1. Real-world user data (CrUX) matters more than lab scores for Google ranking.
Top improvements: (1) Optimize images — use WebP, compress, set dimensions. (2) Use a CDN to cut TTFB. (3) Reduce JavaScript. (4) Preload critical fonts and hero images. (5) Set explicit size attributes on images to prevent CLS. PageGuard's report shows exactly which issues to fix.