Loading Performance Best Practices

Strategies to improve website loading performance and user experience.

Core Web Vitals

Largest Contentful Paint (LCP)

• Optimize server response times
• Remove render-blocking resources
• Optimize images and media

First Input Delay (FID)

• Minimize JavaScript execution time
• Use web workers for heavy computations
• Optimize third-party scripts

Cumulative Layout Shift (CLS)

• Include size attributes on images and videos
• Reserve space for dynamic content
• Use CSS aspect-ratio property

Optimization Strategies

Resource Loading

• Implement critical resource hints
• Use preload for important resources
• Defer non-critical JavaScript

Code Splitting

• Split code by routes
• Implement dynamic imports
• Use tree shaking to remove unused code

Caching Strategies

• Implement service workers
• Use HTTP caching headers
• Consider edge caching solutions

Monitoring

Performance Metrics

• Use Lighthouse for auditing
• Monitor real user metrics (RUM)
• Set up performance budgets

Tools and Testing

• Use WebPageTest for detailed analysis
• Implement continuous performance monitoring
• Test on various devices and networks