Next.js is a full-stack React framework built by Vercel. Plain React is only a UI library — it has no built-in routing, no server rendering, no data-fetching conventions, and no bundler configuration out of the box. Next.js fills in exactly those gaps, so you get a production-ready application structure from the first create-next-app command.
What Next.js adds on top of React
- File-based routing — a file's location in the
app/folder becomes its URL, no router library to configure. - Multiple rendering strategies — static generation, server-side rendering, incremental static regeneration, and Partial Prerendering, chosen per route.
- Server Components & Server Actions — run components and data mutations directly on the server, shipping less JavaScript to the browser.
- Built-in optimizations — automatic image optimization (
next/image), font optimization (next/font), and script loading. - API routes / Route Handlers — write backend endpoints in the same project, no separate server needed.
- Turbopack — a Rust-based bundler (stable as of Next.js 16) that replaced Webpack as the default, dramatically speeding up local development and builds.
React vs Next.js in one table
| Plain React (e.g. Vite) | Next.js | |
|---|---|---|
| Routing | Add React Router yourself | Built-in, file-based |
| Rendering | Client-side only by default | SSR, SSG, ISR, PPR — your choice per route |
| Data fetching | useEffect / a library | fetch() directly in Server Components |
| Backend | Needs a separate server | Route Handlers in the same project |
| SEO | Harder — client renders after load | Easy — HTML is ready on first response |
| Deployment | Any static host | Vercel, or any Node/Docker host |
When to reach for Next.js
Choose Next.js when you need good SEO, fast initial page loads, server-rendered content, or a full-stack app without standing up a separate backend. For a purely internal dashboard or a tool that lives entirely behind a login where SEO doesn't matter, a plain React SPA (Vite) can be simpler.
Who uses it
Next.js powers production sites at companies like Netflix, TikTok, Twitch, Notion, and Nike — it is currently the most widely adopted React framework in the ecosystem, according to the annual State of JS and State of React surveys.