next vs astro

meta-framework

astro

Next.js and Astro represent two fundamentally different approaches to building web applications. Next.js is a full-stack React meta-framework optimized for interactive, data-driven applications with server-side rendering, API routes, and rich client-side state management. Astro is a content-first framework built around a zero-JavaScript-by-default philosophy, using an islands architecture to selectively hydrate interactive components only when needed.

This comparison matters because choosing between them directly impacts your application's performance profile, developer experience, and infrastructure costs. Next.js targets developers building e-commerce platforms, SaaS dashboards, and dynamic web applications where interactivity and real-time data are paramount. Astro appeals to teams creating marketing sites, blogs, documentation portals, and content-heavy platforms where speed, SEO, and minimal JavaScript are the priority.

Head-to-Head

JavaScript Bundle Size→ astro wins

Ships 80-150 KB of JavaScript on first load due to React runtime, hydration code, and framework overhead. A typical homepage weighs ~257 KB total with automatic code-splitting and route-based chunking. Unavoidable baseline for interactive features.

astro

Delivers 0-5 KB JavaScript by default with static HTML output. Typical homepage is ~91 KB total. Uses partial hydration via islands architecture—only interactive components ship JS. Achieves 65-75% smaller bundles than Next.js for equivalent content.

Runtime Architecture→ astro wins

React-centric with Server Components, client components, and full hydration by default. Provides SSR, ISR, SSG modes with automatic switching. Requires Node.js runtime or Edge for dynamic features. Heavy runtime but powerful for stateful apps.

astro

Static-first with optional islands for interactivity. Supports any UI framework (React, Vue, Svelte) in the same project. No runtime required for static output—deploys as plain HTML/CSS/JS. Minimal client-side framework code unless explicitly added.

Build Performancetie

Builds 10-page site in ~41s with Turbopack, 20-page in ~12s (Next.js 16). Generates 103 MB cache. Dev server starts in 2.1s. Fast incremental builds but heavier disk footprint. Optimized for large-scale applications.

astro

Builds 10-page site in ~45s, but cold start is 3.2s with Vite. Generates 42 MB cache (59% smaller). Dev server starts in 0.8s. Faster iteration for content changes but similar production build times at scale.

Core Web Vitals→ astro wins

Lighthouse scores 85-98 with LCP of 1.4-2.1s and TBT of 50-180ms due to JavaScript hydration overhead. Improved with Server Components but still ships React runtime. Solid performance but not optimal for content sites.

astro

Consistently achieves perfect 100 Lighthouse scores with LCP of 0.8-1.2s and 0ms TBT. No hydration delay for static content. 2-3x faster page loads than Next.js for content-heavy sites. Unmatched for performance-critical marketing pages.

Developer Experiencetie

Comprehensive full-stack framework with API routes, middleware, authentication patterns, and database integrations. Rich ecosystem of React libraries. More boilerplate but handles complex app logic elegantly. TypeScript support built-in with 3s checks.

astro

Minimal API surface with component-based architecture. Content Collections provide type-safe content handling (39ms). Vite-powered dev server is snappy. Less opinionated about data fetching and state management. Simpler for static sites but requires external solutions for dynamic features.

Ecosystem & Community→ next wins

127k+ GitHub stars with massive React ecosystem. Vercel-backed with extensive documentation, deployment optimizations, and commercial support. Dominant choice for production applications with proven scalability at enterprise level.

astro

Growing community but significantly smaller. Fewer third-party integrations and plugins. Strong documentation for core features but less community content for edge cases. Suitable for established patterns but less battle-tested for complex scenarios.

Verdict

Choose Astro when building content-focused sites where performance, SEO, and minimal JavaScript are non-negotiable requirements. Marketing pages, blogs, documentation sites, and portfolios benefit dramatically from Astro's zero-JS defaults and perfect Lighthouse scores. You'll achieve 50-80% hosting cost savings through static deployment, 2-3x faster page loads, and simpler deployment to any CDN. The islands architecture lets you add interactive components surgically without compromising the performance budget.

Choose Next.js when building interactive applications requiring server-side rendering, real-time data, authentication, API routes, or complex client-side state management. E-commerce platforms, SaaS dashboards, social media apps, and data-driven tools justify the larger bundle size with robust full-stack capabilities. The React ecosystem, Vercel deployment optimizations, and proven scalability at enterprise level make Next.js the pragmatic choice despite heavier JavaScript payloads. If your application is primarily interactive rather than content-driven, Next.js delivers better developer experience and architectural patterns.

When to Use Each

If you are building a marketing website with mostly static content and occasional interactive elements → use Astro because you'll achieve perfect Lighthouse scores with 90% less JavaScript while still adding React/Vue components only where needed for forms or widgets.

If you are building an e-commerce platform with user authentication, shopping cart state, and dynamic product pages → use Next.js because you need SSR for personalization, API routes for checkout logic, and the React ecosystem for complex UI state management.

If you are building a technical documentation site with search and syntax highlighting → use Astro because static generation with Content Collections provides type-safe content handling, instant page loads, and you can add interactive search as a single island component.

If you are building a SaaS dashboard with real-time updates, user roles, and data visualization → use Next.js because Server Components enable efficient data fetching, middleware handles authentication, and the full-stack architecture supports WebSocket integration and database queries.

Learn More

next →astro →

Head-to-Head

JavaScript Bundle Size→ astro wins

astro

Runtime Architecture→ astro wins

astro

Build Performancetie

astro

Core Web Vitals→ astro wins

astro

Developer Experiencetie

astro

Ecosystem & Community→ next wins

astro

Verdict

When to Use Each