Free Core Web Vitals Comparator
Compare two pages side-by-side using Google Lighthouse data: LCP, CLS, INP, and Performance Score.
Free Core Web Vitals Comparator
Compare two versions of a page — before and after an optimization, old vs new design, or your page vs a competitor's — across all Core Web Vitals metrics on both desktop and mobile simultaneously.
How Core Web Vitals Influence Free Organic Rankings
LCP Below 2.5s = Rankings Edge
Google's own Page Experience documentation confirms that pages passing Core Web Vitals thresholds may receive a rankings boost in closely contested queries. LCP is the most impactful of the three metrics.
CLS Below 0.1 = Trust Signal
Layout instability — buttons moving after ads load, text jumping around images — drives bounce rates. Google measures CLS at the 75th percentile of real user sessions via Chrome User Experience Report data.
INP Below 200ms = Engagement
INP replaced FID in 2024 as the responsiveness metric. It measures the worst interaction delay across the full page visit. Heavy JavaScript event handlers are the primary cause of INP failures.
Using the Comparator for Competitive Intelligence
Enter your page as URL A and a direct competitor as URL B. The side-by-side scores immediately reveal whether your competitor's rankings advantage partly comes from a technical performance edge. If they score a 94 on mobile and you score a 57, that gap is a direct ranking factor difference — one that can be closed with targeted optimization rather than more content or link building. Pair the findings with our Free JavaScript Rendering Lighthouse Test to identify which scripts are causing the performance gap.