Website Performance Profiler

Measure Core Web Vitals (LCP, INP, CLS) and site speed locally in real time, with actionable recommendations.

Measure, diagnose, and optimize real-world website performance directly in Google Chrome. Website Performance Profiler is a lightweight, privacy-first developer tool that captures Core Web Vitals, page load timing, resource waterfalls, and actionable optimization insights in real time. Whether you are a web developer, SEO specialist, site reliability engineer, or performance auditor, Website Performance Profiler gives you instant visibility into what is slowing down your web pages—without opening heavyweight DevTools panels or sending data to external servers. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🚀 KEY FEATURES & CAPABILITIES ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1. REAL-TIME CORE WEB VITALS (CWV) Get immediate Google Core Web Vitals diagnostics adhering to official web.dev thresholds: • LCP (Largest Contentful Paint): Pinpoints when the main visual content is rendered and identifies the specific LCP DOM element. • INP (Interaction to Next Paint): Measures real user responsiveness and highlights laggy interaction events. • CLS (Cumulative Layout Shift): Tracks layout instability and displays the exact elements causing shifts. • Supplementary Metrics: First Contentful Paint (FCP), Time to First Byte (TTFB), and First Input Delay (FID fallback). 2. SIDE PANEL & POPUP COMPACT HUD Seamlessly switch between two intuitive viewing modes: • Instant Popup: Click the extension icon or press Alt+Shift+P for a rapid 5-second health check and overall performance score. • Dedicated Side Panel: Keep metrics visible alongside your page as you browse, test interactions, or inspect mobile viewports. 3. RESOURCE WATERFALL & ASSET AUDITOR Break down page weight and load stages with visual clarity: • Filter resources by Scripts (JS), Stylesheets (CSS), Images, Fonts, and Fetch/XHR requests. • Identify render-blocking resources before they delay First Paint. • Inspect caching headers, compression (gzip/brotli), and transfer sizes. 4. "WHAT-IF" SCRIPT BLOCKER SIMULATOR Test optimization hypotheses in seconds without editing production code: • Block heavy third-party tags, analytics trackers, or slow scripts. • Reload the page to instantly observe how much LCP and total load time improve when those scripts are removed. 5. PR-READY EXPORTS & AUDIT REPORTS Share performance findings effortlessly across your engineering team: • Markdown Report: Formatted with tables, emojis, and CWV statuses—ready to paste directly into GitHub Pull Requests or Jira tickets. • Detailed HTML Report: Comprehensive audit sheet with visual charts and priority recommendations. • Machine-Readable JSON: Export raw metric snapshots for CI/CD comparisons and performance budgets. 6. DIGITAL CARBON FOOTPRINT ESTIMATION Understand the ecological footprint of your web assets: • Calculates estimated grams of CO2 per page load based on data transfer and network energy consumption. • Encourages greener, leaner web architecture. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🔒 100% PRIVATE & CLIENT-SIDE ONLY ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • ZERO Data Collection: No tracking, no user profiling, no remote telemetry. • ZERO External Servers: 100% of metric calculations, DOM inspections, and audits execute directly within your local browser sandbox. • NO Accounts or Sign-ups: Install and immediately profile any web page or localhost environment. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🛠 HOW TO USE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1. Navigate to any website or local development server (e.g. http://localhost:3000). 2. Click the Website Performance Profiler icon in your toolbar, or press Alt+Shift+P (Option+Shift+P on Mac). 3. View your instant Performance Score and Core Web Vitals health badges. 4. Click "Open Side Panel" for in-depth waterfalls, asset breakdowns, script blocking simulations, and PR markdown exports. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ⚡ BUILT FOR MODERN DEVELOPERS ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Designed and maintained by Chalwiha Technologies Private Limited. We build fast, reliable, privacy-respecting software tools for modern web professionals. For feature requests, feedback, or documentation, visit: https://www.chalwiha.com/