This section contains comprehensive guides for measuring, analyzing, and optimizing frontend performance. Performance is crucial for user experience, SEO, and conversion rates.
- LCP (Largest Contentful Paint): ≤ 2.5s
- FID (First Input Delay): ≤ 100ms
- CLS (Cumulative Layout Shift): ≤ 0.1
- TTFB (Time to First Byte): ≤ 600ms
- FCP (First Contentful Paint): ≤ 1.8s
- SI (Speed Index): ≤ 3.4s
| Tool | Purpose | Best For |
|---|---|---|
| Lighthouse | Comprehensive performance auditing | Overall performance analysis |
| React Profiler | Component-level performance | React app optimization |
| Bundle Analyzer | Bundle size analysis | Code splitting & tree shaking |
| WebPageTest | Real-world performance testing | Production performance monitoring |
- Audit your current performance with Lighthouse
- Profile your React components to identify bottlenecks
- Analyze your bundle to find optimization opportunities
- Test from multiple locations with WebPageTest
- Minimize render-blocking resources
- Optimize critical CSS
- Use resource hints (preload, prefetch, preconnect)
- Implement code splitting
- Use modern formats (WebP, AVIF)
- Implement lazy loading
- Optimize image dimensions
- Use responsive images
- Minimize bundle size
- Implement tree shaking
- Use dynamic imports
- Optimize third-party libraries
- Enable compression (Gzip/Brotli)
- Use CDN for static assets
- Implement caching strategies
- Minimize HTTP requests
- Assets Optimization - Image, SVG, and font optimization
- Build & Deploy - Bundle optimization and deployment
- Network & API - API optimization and caching