What's the difference between Astro and Next.js?

Next.js is a React application framework that runs JavaScript on a server to render pages. Astro is a content framework that builds pages into plain HTML files before anyone visits. They solve different problems: Next.js is built for web applications with state, user accounts, and dynamic data; Astro is built for content-driven sites that need to load fast and stay out of the way. Both can technically build either kind of site, but each is wrong for the other's job.

Is Astro better than Next.js for SEO?

For most content-driven sites, yes — and the reason is architectural, not configurable. Astro ships plain HTML to the browser on first request, which is the shape Google's crawlers prefer and which Core Web Vitals reward. Next.js can match this with static export or careful server-side rendering, but the framework's default shape ships JavaScript that hydrates in the browser, which adds load time and complexity. For a UK small business that wants to rank without fighting the framework, Astro starts SEO-friendly by default. Next.js can get there; Astro is already there.

When should I choose Next.js over Astro?

Choose Next.js when your site needs to behave like an application — logged-in user accounts, real-time dashboards, complex stateful interactions, search across user-generated content, or anywhere a single-page React experience genuinely improves the product. SaaS dashboards, booking platforms, marketplaces, and member areas are Next.js territory. A brochure site, service business, consultancy, or content publisher is not.

Can I migrate from Next.js to Astro?

Yes, and it's usually a cleaner migration than WordPress to Astro because both frameworks already speak the same component vocabulary. If the existing Next.js site is mostly content pages with a small amount of interactivity, the migration is often a matter of converting React components to Astro components and bringing the pages across. The harder parts are anywhere the site is doing application work — those features either get cut, get reimplemented, or stay on Next.js while the content layer moves.

Is Next.js overkill for a business website?

For most UK small business sites, yes. Next.js was built at Vercel to solve the problems of large-scale React applications: data fetching patterns, dynamic routing, server components, edge functions, incremental static regeneration. None of these are problems a service business website has. You're paying the complexity tax of an application framework to ship a brochure site. The result still works, but you're carrying weight you'll never lift.

Does Astro support React components like Next.js?

Yes. Astro can render React components, Vue components, Svelte components, Solid components — and ship them as HTML by default, with interactivity opted in per component. This is the part most developers don't realise on first read: you don't have to choose between Astro and React. You use React where it earns its keep and ship HTML for everything else. Next.js makes React the default for every page; Astro makes HTML the default and React the exception.

Astro vs Next.js for Small Business: Honest Comparison

Both are excellent. Both are wrong for most of the audience choosing between them. Next.js is a React application framework that ships JavaScript and renders on a server. Astro ships HTML and gets out of the way. Pick the wrong shape and you pay for it for years — in load time, in hosting bills, in maintenance hours, in the gap between what your site does and what your business actually needs. The honest answer for a UK small business sits in the trade-off, not the marketing.

Why This Comparison Gets Written Badly

Everyone writing this comparison has skin in the game. Vercel built Next.js, hosts most of the high-profile sites that run on it, and benefits commercially every time a developer picks it. The Astro core team is paid by the same kind of ecosystem incentives in the opposite direction. The articles you find ranking for “Astro vs Next.js” are mostly written by developers who picked one and want to justify the choice, or by content marketers writing for one of the two companies.

I build on Astro for paying clients and I’ll tell you when it’s the wrong answer. The framing below is the same one I’d give you over the phone if you sent me a site and asked which to build it on. There’s a defensible answer either way — and the honest version depends on what your site actually has to do.

A framework is a shape, not a feature. The shape you pick decides what your site is good at for the next five years.

What Astro and Next.js Are Each Built For

Next.js is a React framework. React was built by Facebook to solve the problem of complex, stateful user interfaces — comment threads, news feeds, dashboards, anywhere the page needs to change in response to a user doing something. Next.js extends React with the infrastructure a serious React application needs: server-side rendering, static export, dynamic routing, edge functions, data fetching patterns, the works. It’s the framework you reach for when you’re building Notion, or Vercel itself, or a SaaS product with logged-in users.

Astro started from the opposite question. The Astro team looked at what most content-driven sites actually do — render some HTML, ship it to a browser, get out of the way — and asked why we were building those sites with the same tools used for stateful applications. Astro builds your pages into plain HTML files at build time. When a visitor arrives, the server sends the finished file and stops. JavaScript is opt-in per component: you ship it only where it earns its keep.

The split decides almost every downstream property of the platform.

90%+ less JavaScript

typical Astro page payload vs an equivalent Next.js page for the same content

Next.js renders pages and ships React to the browser to hydrate them. Even with static export, the framework’s default shape assumes you want client-side interactivity available. Astro renders pages and ships nothing by default. The result is a site that loads faster, costs less to host, and degrades gracefully when JavaScript fails — which it does on real-world mobile networks more often than developer dashboards suggest.

Speed: Astro vs Next.js for Content Sites

If your site is mostly content — service pages, blog posts, product information, about pages, contact forms — Astro will load measurably faster than the same site built in Next.js. The reason is structural. Astro pages are pre-rendered HTML. Next.js pages, even when statically exported, ship a JavaScript bundle that has to download, parse, and execute before the page becomes interactive. The difference is most visible on mobile devices on slower networks, which is where the UK small-business audience actually is.

I migrated a marketing site from Next.js to Astro last year that ran on the same content, on the same hosting, with the same imagery. The Lighthouse performance score went from 78 to 99. Largest Contentful Paint dropped from 2.4 seconds to 0.6 seconds. The site didn’t look any different to a human eye — but Google’s ranking signals noticed, and so did the visitors who didn’t bounce off the loading spinner.

Where the speed gap doesn’t matter is when the site is fundamentally an application. A SaaS dashboard that loads once and runs for an hour doesn’t benefit from shaving 1.8 seconds off the initial render. The user is going to spend forty-five minutes inside the interface. The optimisation that matters is the interactive responsiveness once they’re in, which is exactly what React and Next.js are built for.

The honest framing: speed gaps matter most when first impressions matter most. A brochure site, a service business, a content publisher — these live and die on first impressions. A logged-in product does not.

Cost: Astro vs Next.js Over Five Years

Next.js hosting has a specific shape. The framework can run statically (output as files, host anywhere) or as a Node.js server (handles dynamic rendering, requires a runtime). Most Next.js sites end up on Vercel because Vercel is built for exactly this stack — but Vercel pricing scales aggressively with traffic and serverless function calls, and a successful Next.js site on the Pro plan ($20/month plus usage) can run to several hundred dollars a month at scale. Self-hosting Next.js on AWS or DigitalOcean is doable but moves operational complexity onto whoever runs the site.

Astro builds to static files by default. The output is plain HTML, CSS, and a small amount of JavaScript. You can host it on Netlify’s free tier, Cloudflare Pages’ free tier, GitHub Pages, or any static host — and for typical UK small-business traffic levels, you pay nothing. The site that hosts this article runs entirely on the Netlify free tier and has done so through every traffic spike we’ve thrown at it.

A five-year hosting comparison for a UK small business site:

Next.js on Vercel: $240-$600/year base, more with traffic. £1,000-£2,500 over five years.
Astro on Netlify free tier: £0. Free at the traffic levels small businesses actually see.

The build cost is similar between the two — a competent developer charges similar rates for either stack — but the running cost diverges sharply. The five-year picture rewards Astro for any site that doesn’t genuinely need application infrastructure.

SEO: Astro vs Next.js for Search Rankings

Next.js can be configured to be SEO-friendly. It supports static export, server-side rendering with proper meta tags, sitemaps, structured data, canonical URLs — everything modern SEO needs. The framework doesn’t fight you. But the framework also doesn’t help you: SEO on Next.js is implementation work that a developer has to remember to do correctly on every page.

Astro starts SEO-friendly. The framework’s default shape is the shape Google prefers: HTML on first request, semantic markup, predictable URLs, fast Core Web Vitals out of the box. You can still mess it up if you try — set output: 'server' and forget to configure trailing slashes, and you’ll re-create the URL drift problems WordPress is famous for. But you have to work to break it.

The bigger SEO argument is Core Web Vitals. Google has been ranking sites on Largest Contentful Paint, Cumulative Layout Shift, and Interaction to Next Paint for years. A Next.js site can pass these metrics with careful work. An Astro site passes them by default. For a UK small business that doesn’t have a senior frontend engineer keeping the lighthouse audit clean, the architectural advantage is significant.

The best SEO strategy is to build on something that’s hard to break. Astro is hard to break. Next.js is easy to break unless someone is paying attention.

When Next.js Is the Right Answer

I’ll name the cases where Next.js wins, because they exist and they’re real.

Build on Next.js when:

Your site is genuinely an application. Logged-in user accounts, persistent state across pages, real-time data, a dashboard interface, anywhere the page changes shape based on who’s looking at it. This is the use case Next.js was built for and it’s still the best framework for the job.
You’re shipping a React product. If you already have a React codebase — components, hooks, state management, internal libraries — Next.js is the natural extension. Trying to bring that into Astro means rewriting the parts that don’t speak Astro’s component model.
You need full SSR with dynamic data on every request. Ecommerce product pages that show real-time stock, personalised landing pages that change per visitor, content gated behind authentication. Astro can do server rendering, but the natural shape of the framework is static-first.
Your team is React-fluent and not interested in learning a second component model. This is a real consideration. Astro’s component syntax is close to HTML with frontmatter; React developers adopt it quickly, but if the team’s existing throughput is already at Next.js velocity, the switch has to earn the disruption.
You’re building inside a Vercel-first organisation. If the rest of the company runs on Vercel infrastructure, Next.js is the path of least friction. The platform optimises hard for its own framework.

For a SaaS product, an internal dashboard, a marketplace, or a complex web application, Next.js is the right architectural choice. Trying to make Astro do that job is the same mistake as trying to make Astro do WordPress’s job in the other direction.

When Astro Is the Right Answer

For everything else, Astro wins on every axis that matters to a UK small business website.

Build on Astro when:

Your site is content. Service pages, blog posts, product information, about pages, case studies, landing pages. The vast majority of UK small business sites fall here.
Page speed is a ranking and conversion variable. Mobile-first audiences, organic search dependence, anywhere first-impression load time matters. The architectural advantage is largest where speed matters most.
You want to host cheaply or freely. Static output on Netlify or Cloudflare Pages costs nothing for typical small-business traffic. Vercel’s pricing makes Next.js economically punishing for content sites that succeed.
You don’t want to maintain JavaScript dependencies you don’t need. Astro lets you ship interactive React or Vue components only where they earn their keep. Most pages ship zero JavaScript, which means almost nothing to break, almost nothing to update, almost no security surface.
The site is going to outlive whoever built it. Plain HTML is the most portable artefact on the web. Astro sites can be moved, archived, or rebuilt by anyone who reads HTML and Markdown. Next.js sites need someone who reads React.

How to Decide Between Astro and Next.js

Ask three questions, in order.

One: Does the site genuinely need to behave like an application? Logged-in users, real-time data, complex state, anything beyond a contact form. If yes, Next.js. If no, continue.

Two: Is your team committed to React for everything, including pages that don’t need it? If yes, Next.js is the path of least disruption. If no, continue.

Three: Is page load speed a real ranking or conversion variable for the site? If yes, Astro. If you’re not sure, ask Google’s PageSpeed Insights and look at the mobile score. If it’s below 90, speed is a variable whether or not you’ve been treating it as one.

If two of the three point to Astro, the choice is Astro. If two point to Next.js, the choice is Next.js. If it’s split one-and-one with the third unclear, the deciding question is usually the first: does this site need to be an application? Most don’t, and the framing changes once you stop assuming it does.

The Honest Verdict for UK Small Business Sites

If your business is a service business, a trade, a consultancy, a B2B supplier, a small ecommerce shop, a marketing site for a software product, or any content-driven site that mostly sits there and waits for people to find it — Astro is the right architecture. The speed gap is real, the cost gap compounds, the SEO advantage is architectural, and the maintenance burden is closer to zero.

If your business is a SaaS product, a marketplace, a booking platform, or anywhere the site needs to be an application — Next.js is the right framework. Astro can technically do the job, but you’d be fighting the shape of the tool.

The mistake most prospects make is reaching for Next.js because it’s what their developer friend recommended for a “modern” site. Modern doesn’t mean React-everywhere. Modern means the right shape for the job. For 80% of the UK small businesses I talk to, that shape is Astro — and the proof is the load time, the hosting bill, and the absence of three a.m. plugin update emergencies.

The Astro vs WordPress comparison covers the same territory from a different angle — what to do if you’re currently on WordPress instead of weighing up Next.js. The what is an Astro website piece is the plain-English foundation underneath both. If you’d rather skip the reading and tell me what you have now, send me the URL and I’ll give you the honest answer for your specific situation — including “stay on Next.js” if that’s what your site genuinely needs.