Web Performance Optimization

Website performance directly impacts user experience, SEO rankings, and conversion rates. Let's explore proven techniques to make your websites lightning fast!

Why Performance Matters

• User Experience - 53% of users abandon sites that take over 3 seconds to load
• SEO - Google uses page speed as a ranking factor
• Conversions - Amazon found that every 100ms of latency cost them 1% in sales
• Accessibility - Faster sites work better on slower connections

Core Web Vitals

Google's Core Web Vitals measure user experience:

1. Largest Contentful Paint (LCP)

Measures loading performance. Aim for under 2.5 seconds.

How to improve:

• Optimize images (use WebP, lazy loading)
• Minimize CSS and JavaScript
• Use CDN for static assets
• Implement server-side rendering

2. First Input Delay (FID)

Measures interactivity. Aim for under 100ms.

How to improve:

• Break up long JavaScript tasks
• Use web workers for heavy computations
• Minimize third-party scripts
• Implement code splitting

3. Cumulative Layout Shift (CLS)

Measures visual stability. Aim for under 0.1.

How to improve:

• Set dimensions for images and videos
• Avoid inserting content above existing content
• Use transform animations instead of layout animations

Image Optimization

Images often account for most of a page's weight:

<!-- Use modern formats -->
<picture>
  <source srcset="image.webp" type="image/webp">
  <source srcset="image.jpg" type="image/jpeg">
  <img src="image.jpg" alt="Description" loading="lazy">
</picture>

<!-- Responsive images -->
<img 
  srcset="small.jpg 480w, medium.jpg 800w, large.jpg 1200w"
  sizes="(max-width: 600px) 480px, (max-width: 1000px) 800px, 1200px"
  src="medium.jpg"
  alt="Description"
>

Code Splitting

Split your JavaScript bundles:

// Dynamic imports
const module = await import('./heavy-module.js')

// Route-based splitting in Vue
const routes = [
  {
    path: '/dashboard',
    component: () => import('./views/Dashboard.vue')
  }
]

Lazy Loading

Load content only when needed:

<template>
  <!-- Lazy load images -->
  <img src="image.jpg" loading="lazy" alt="Description">
  
  <!-- Lazy load components -->
  <Suspense>
    <template #default>
      <HeavyComponent />
    </template>
    <template #fallback>
      <LoadingSpinner />
    </template>
  </Suspense>
</template>

<script setup>
import { defineAsyncComponent } from 'vue'

const HeavyComponent = defineAsyncComponent(() =>
  import('./HeavyComponent.vue')
)
</script>

Caching Strategies

Implement effective caching:

// Service Worker caching
self.addEventListener('fetch', (event) => {
  event.respondWith(
    caches.match(event.request).then((response) => {
      return response || fetch(event.request)
    })
  )
})

// HTTP caching headers
Cache-Control: public, max-age=31536000, immutable

Minimize JavaScript

Reduce JavaScript execution time:

1. Tree shaking - Remove unused code
2. Minification - Compress code
3. Defer non-critical scripts - Use defer or async
4. Remove unused dependencies - Audit your package.json

Database Optimization

For backend performance:

• Use indexes - Speed up queries
• Implement caching - Redis, Memcached
• Connection pooling - Reuse database connections
• Query optimization - Avoid N+1 queries

Monitoring

Track performance over time:

• Lighthouse - Automated audits
• WebPageTest - Detailed performance analysis
• Real User Monitoring (RUM) - Track actual user experience
• Chrome DevTools - Profile and debug performance

Quick Wins Checklist

• Enable gzip/brotli compression
• Minify CSS and JavaScript
• Optimize images (WebP, compression)
• Implement lazy loading
• Use a CDN
• Enable browser caching
• Reduce HTTP requests
• Inline critical CSS
• Defer non-critical JavaScript
• Optimize fonts (font-display: swap)

Conclusion

Performance optimization is an ongoing process. Start with the quick wins, measure the impact, and continuously improve. Your users (and your business) will thank you!