Google PageSpeed Insights
Official Google tool that analyzes your webpage on mobile and desktop devices. Provides detailed performance scores based on Core Web Vitals and actionable recommendations for improvement.
GTmetrix
Comprehensive performance analysis tool with waterfall charts, video playback, and historical tracking. Test from multiple locations worldwide with detailed breakdowns of every resource.
WebPageTest
Advanced testing tool with extensive customization options. Test from real browsers in different locations, simulate various connection speeds, and get detailed filmstrip views of page loading.
Lighthouse (Chrome DevTools)
Built into Chrome DevTools, Lighthouse provides automated audits for performance, accessibility, progressive web apps, SEO, and best practices. Run tests directly in your browser.
Pingdom Website Speed Test
User-friendly performance testing with clear visualizations. Test from multiple global locations and get easy-to-understand performance grades and recommendations.
Key Performance Metrics to Monitor
First Contentful Paint (FCP)
Time until first text or image is painted. Target: <1.8s. Measures initial rendering speed.
Largest Contentful Paint (LCP)
Time until largest content element loads. Target: <2.5s. Core Web Vital for page load performance.
First Input Delay (FID)
Time until page responds to user interaction. Target: <100ms. Measures interactivity.
Cumulative Layout Shift (CLS)
Measures visual stability. Target: <0.1. Prevents annoying layout shifts during page load.
Time to Interactive (TTI)
Time until page is fully interactive. Target: <3.8s. When all scripts have loaded and page is responsive.
Total Page Size
Total size of all resources. Target: <1-3MB. Includes HTML, CSS, JS, images, fonts.