Page Performance Analyzer

Page Performance Analyzer scores any webpage you visit and tells you exactly what's slowing it down — using Chrome's own Performance APIs, entirely in your browser. No account, no server, no data leaves your machine. Click the toolbar icon on any site to get a 0–100 performance score plus a prioritized list of fixes, each explained in plain English with the actual measured numbers behind it. WHAT IT MEASURES - Core Web Vitals — Largest Contentful Paint (LCP), Cumulative Layout Shift (CLS), First Contentful Paint (FCP) - Server responsiveness — Time to First Byte (TTFB) - Page weight & request count, broken down by resource type - Render-blocking scripts and stylesheets in <head> - Third-party domains the page depends on - Uncompressed text assets (JS/CSS/fetch responses missing gzip/brotli) - Image issues — missing width/height (a common cause of layout shift), missing lazy-loading below the fold, missing alt text - DOM size and main-thread "long tasks" that make a page feel unresponsive - Whether the page is served over HTTPS WHY IT'S DIFFERENT Most performance tools just show you numbers. This one tells you what each number means, whether it's good or bad, and what specifically to change — no interpretation required. HOW TO USE IT 1. Visit any website. 2. Wait a couple of seconds after the page loads — the toolbar badge shows the score once ready. 3. Click the icon for the full breakdown. 4. Click the refresh button to re-run the analysis any time, including right after you make a fix. PRIVACY This extension reads performance timing data from the page you're actively viewing to compute your report. It does not collect, store, or transmit any browsing data to any server — everything happens locally in your browser and is discarded when you close the popup. Built for developers, marketers, and site owners who want a fast, honest read on page performance without opening DevTools.