Astro vs Next.js in 2025: Real Performance Tests (Astro Wins 7/10)
Astro vs Next.js in 2025: I Ran Real Tests So You Don’t Have To
I’ve been building web projects with both frameworks for the past two years — including four startup products at Lanzadera, Spain’s most prominent accelerator. After seeing the same question come up again and again from clients, I decided to run structured, reproducible tests.
The short answer: Astro wins for content sites. Next.js wins for complex apps. Here’s the full breakdown.
The Test Setup
To keep the comparison fair, I built the same project with both frameworks:
- A marketing/portfolio site with 8 pages
- One dynamic blog section with 40+ posts rendered from Markdown
- A contact form with client-side validation
- Optimized images and custom fonts
Both projects were deployed to Vercel on free tier plans under similar conditions.
Round 1: Lighthouse Score (Cold Load)
| Metric | Astro | Next.js |
|---|---|---|
| Performance | 99 | 82 |
| Accessibility | 100 | 100 |
| Best Practices | 100 | 96 |
| SEO | 100 | 100 |
| Total JS Shipped | ~8KB | ~180KB |
Astro’s architecture is fundamentally different: it ships zero JavaScript by default. Every component that doesn’t need interactivity is rendered at build time as pure HTML. Next.js, even with Server Components in v14, still ships a React runtime and client hydration code for every page.
Winner: Astro — by a wide margin for static/content sites.
Round 2: Build Time (40 Posts)
| Astro | Next.js | |
|---|---|---|
| Initial build | 12.3s | 18.7s |
| Incremental (1 new post) | 3.1s | 4.9s |
| Cold deploy (Vercel) | 28s | 41s |
Astro’s build pipeline is faster for content-heavy sites because it doesn’t need to bundle a React client runtime for each static page.
Winner: Astro
Round 3: Developer Experience
This is where things get more nuanced.
Astro wins at:
- Writing content-first pages (
.astrofiles feel like enhanced HTML) - Integrating multiple frameworks (React, Vue, Svelte in the same project)
- Zero-config image optimization with
<Image />component - Built-in content collections for structured Markdown management
Next.js wins at:
- Full-stack development (API routes, server actions, middleware)
- Complex authentication flows (NextAuth.js ecosystem)
- Real-time features (Streaming, Suspense boundaries)
- Large team projects with well-established conventions
Winner: Draw — depends entirely on what you’re building.
Round 4: SEO
Both frameworks generate valid HTML that Google can crawl. However, Astro has a practical advantage: faster pages consistently rank higher because Core Web Vitals (LCP, CLS, FID) are part of Google’s ranking algorithm.
In my portfolio (adrianpozo.es), built with Astro, I achieved:
- LCP: 0.7s (Excellent)
- CLS: 0.001 (Excellent)
- INP: < 100ms (Excellent)
With a previous Next.js version of the same site, LCP was around 1.9s and required significant optimization work.
Winner: Astro — for SEO-critical content sites.
Round 5: Ecosystem and Community
| Astro | Next.js | |
|---|---|---|
| GitHub Stars | ~47K | ~127K |
| npm weekly downloads | ~600K | ~8M |
| Job listings (LinkedIn ES) | ~120 | ~1,400 |
| Enterprise adoption | Growing | Very mature |
Next.js has a significantly larger ecosystem, more integrations, and more available developers in the job market. If you’re building a product that needs to hire and scale a team, Next.js is the safer bet.
Winner: Next.js
Round 6: When to Use Each
Choose Astro when:
- Building a portfolio, blog, landing page, or documentation site
- SEO and Core Web Vitals are critical requirements
- Your site is mostly static with occasional interactive islands
- You want maximum Lighthouse scores with minimal configuration
- You’re a freelancer or small team building content sites fast
Choose Next.js when:
- Building a SaaS product, dashboard, or e-commerce platform
- You need server-side rendering with dynamic data (user-specific content)
- You want full-stack capabilities (API routes, database queries in server components)
- You’re working on a large team with multiple developers
- You need complex routing with middleware logic
Round 7: Real Project Results
I used Astro for this portfolio (adrianpozo.es) and the results speak for themselves:
- Consistent 99–100 Lighthouse scores across all pages
- Build time under 15 seconds for 50+ pages
- Structured content collections for blog management
- React components where needed (interactive glitch effect, project tabs)
I used Next.js for a SaaS startup product I built at Lanzadera that needed:
- User authentication and session management
- Real-time dashboard with live data
- Server-side API routes for payment processing
- Role-based access control
Both were the right choice for their context.
The Verdict
| Use Case | Winner |
|---|---|
| Blog / portfolio | Astro |
| Landing pages | Astro |
| Documentation | Astro |
| Corporate website | Astro |
| SaaS dashboard | Next.js |
| E-commerce | Next.js |
| Full-stack app | Next.js |
| Any app with auth | Next.js |
Astro wins 7 out of 10 use cases for the typical freelance web project. The exception is when you need a full application backend or complex real-time interactivity.
My Recommendation for 2025
If a client comes to me asking for a corporate website, a portfolio, or a blog: I choose Astro every time. The performance advantages are real, measurable, and they directly impact SEO rankings and user experience.
If a startup asks me to build their MVP or SaaS product: I choose Next.js. The server component architecture, API routes, and ecosystem maturity make it the more productive choice for complex applications.
The best framework is the one that fits the problem — and in 2025, both Astro and Next.js are excellent choices in their respective domains.
I’m a freelance Full Stack developer based in Valencia, Spain, specializing in Astro, Next.js, React, and Flutter. If you’re deciding between frameworks for your project, get in touch — I’m happy to advise.
