Optimizing Performance in Astro

Performance is at the core of Astro’s design philosophy. In this post, we’ll explore how to build lightning-fast websites with Astro.

Why Performance Matters

Fast websites provide:

• Better user experience
• Improved SEO rankings
• Lower bounce rates
• Higher conversion rates

Astro’s Performance Features

Zero JavaScript by Default

Astro ships zero JavaScript to the client by default. This means your pages load instantly, with no JavaScript overhead.

Islands Architecture

When you need interactivity, Astro’s Islands Architecture allows you to add JavaScript only where needed:

---
import Counter from '../components/Counter.jsx';
---

<Counter client:load />

Image Optimization

Astro provides built-in image optimization:

---
import { Image } from 'astro:assets';
import myImage from '../assets/image.jpg';
---

<Image src={myImage} alt="Description" />

Best Practices

1. Use Static Generation

Pre-render your pages at build time for maximum performance:

---
export const prerender = true;
---

2. Optimize Images

Always use Astro’s Image component or optimize images before uploading.

3. Minimize Client-Side JavaScript

Only add interactivity where absolutely necessary.

4. Use Content Collections

Content Collections are optimized for performance and provide type safety.

5. Code Splitting

Astro automatically code-splits your JavaScript, loading only what’s needed.

Measuring Performance

Use tools like:

• Lighthouse
• WebPageTest
• Chrome DevTools

Conclusion

Astro makes it easy to build fast websites. By following these best practices, you can create websites that load instantly and provide an excellent user experience.