Enter any URL and get a real-world performance report for both mobile and desktop in seconds. The analyzer runs your page through Google PageSpeed Insights and surfaces the six metrics that matter most — along with a prioritised list of exactly what to fix and how much time each fix would save.
Why page speed matters
Google uses Core Web Vitals as a direct ranking signal. Slow pages rank lower, bounce harder, and convert worse — a 1-second delay in mobile load time can reduce conversions by up to 20%. More importantly, the metrics this tool measures are the same ones Google's algorithm evaluates: they represent real user experience, not synthetic benchmarks.
Fast pages also reduce infrastructure cost. Fewer bytes sent, less render-blocking work, and leaner JavaScript mean lower CDN egress, better cache hit rates, and less CPU time per visitor on both server and client.
What each metric means
Largest Contentful Paint (LCP) — how long until the biggest visible element (hero image, heading, video poster) is fully rendered. Google's threshold for a good score is under 2.5 seconds. Slow LCP is almost always caused by unoptimised images, render-blocking resources, or a slow server response.
First Contentful Paint (FCP) — the moment any content first appears on screen. Users perceive a page as loading once FCP fires, so a fast FCP reduces perceived wait time even if the full page takes longer.
Total Blocking Time (TBT) — the sum of all time intervals where the main thread was blocked long enough to delay user input. High TBT means the page looks loaded but feels frozen. Heavy JavaScript bundles are the primary culprit.
Cumulative Layout Shift (CLS) — a score for how much the layout jumps around while loading. Ads, lazy-loaded images without dimensions, and late-injected banners are common causes. A CLS above 0.1 is considered poor and directly tanks the user experience on mobile.
Speed Index (SI) — how quickly content is visually populated above the fold. Lower is better; it penalises pages that render incrementally rather than painting a usable view early.
Time to First Byte (TTFB) — the gap between a request being sent and the first byte of the response arriving. High TTFB points to slow server processing, an un-cached response, or a distant origin with no CDN.
Reading the score
The overall performance score (0–100) is a weighted composite of the six metrics above. Google colour-codes ranges: 90–100 is fast (green), 50–89 needs improvement (amber), 0–49 is slow (red). Mobile and desktop scores are shown separately because mobile audits simulate a slower CPU and network — a 90 on desktop with a 45 on mobile is a common pattern for pages with unoptimised images or large JavaScript payloads.
Opportunities
Below the scores, the tool shows up to six top opportunities ranked by the estimated milliseconds they would save. These come directly from Lighthouse's audits and include things like eliminating render-blocking resources, properly sizing images, removing unused JavaScript, enabling text compression, or reducing initial server response time. Each opportunity shows the specific savings so you can prioritise the highest-impact fix first.
How to use it
Paste any public URL (with or without https://) and click Analyze. Results take 10–30 seconds — the tool runs both mobile and desktop audits in parallel. The report shows side-by-side scores and metrics for each strategy, followed by the improvement opportunities.
Free to use, no account required.