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Stop Guessing. Start Diagnosing.
A slow website doesn’t just frustrate users—it kills your Google rankings. Our Core Web Vitals & Speed Forensics engine taps directly into the Google Lighthouse API to give you real-world Chrome UX (CrUX) data, frame-by-frame rendering filmstrips, and exact network bottlenecks.
Decoding Core Web Vitals
Largest Contentful Paint (LCP)
Measures loading performance. It marks the exact millisecond the largest text or image block is fully rendered on the screen.
Cumulative Layout Shift (CLS)
Measures visual stability. It identifies elements that unexpectedly shift around the page while loading, causing user frustration.
Total Blocking Time (TBT)
Measures interactivity. It calculates how long the browser’s main thread was blocked by heavy JavaScript, preventing the user from clicking.
First Contentful Paint (FCP)
The moment the browser renders the very first piece of DOM content (text, image, or SVG), telling the user the site is actually loading.
More Than Just a Speed Test
Render Filmstrips
See exactly what your users see. Our tool generates a millisecond-by-millisecond visual filmstrip of your website rendering on a mobile device, allowing you to spot “white screen” delays instantly.
CrUX Field Data
Lab data is just a simulation. We extract actual Chrome User Experience (CrUX) Report data to show you exactly how real human visitors are experiencing your site globally over the last 28 days.
Network Waterfall Analysis
Uncover the invisible bloat. Review a detailed table of network requests to identify massive uncompressed images, render-blocking third-party scripts, and oversized CSS files.
Diagnostic Opportunities
Don’t just find the problems—fix them. We analyze your DOM size, caching headers, and thread execution times to provide you with actionable, byte-saving opportunities.
Why Page Speed is Your Best SEO Strategy
In modern SEO, speed is not a luxury; it is a prerequisite. Google’s algorithm explicitly uses Core Web Vitals as a ranking signal for both mobile and desktop results.
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Decrease Bounce Rates: A site that loads in 1 second has a bounce rate 3x lower than a site that takes 5 seconds.
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Increase Conversions: Amazon found that every 100ms of latency cost them 1% in sales. Faster pages generate more revenue.
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Crawl Budget: Faster server response times allow Googlebot to crawl and index more of your deep pages in a single visit.
Frequently Asked Questions
What is the difference between Lab Data and Field Data?
Lab data is collected in a controlled environment with predefined device and network settings (like a speed test). Field data (CrUX) is historical data collected from real Chrome users who have visited your site over the last 28 days. Google uses Field data for ranking.
How can I fix a high Cumulative Layout Shift (CLS)?
A high CLS is usually caused by images, ads, or iframes loading without predefined dimensions in the HTML. To fix it, always include width and height attributes on your media, and preload custom fonts to avoid text flashes.
Why does my mobile score differ from my desktop score?
Mobile tests simulate a mid-tier smartphone on a throttled 4G network, which exposes heavy JavaScript processing and large image payloads. Desktop tests assume a fast broadband connection and a powerful CPU. Mobile optimization is critical as Google uses Mobile-First Indexing.
