The Relationship Between React and Next.js

React is a JavaScript library for building user interfaces. Next.js is a framework built on top of React that adds server-side rendering, routing, API routes, and many other features that React alone does not provide.

Think of it this way: React is an engine, Next.js is a complete car. You can build a car yourself using just the engine, but most people are better off with the full package.

What React Gives You

React gives you a component model for building UIs, a state management system, and a virtual DOM for efficient rendering. That is it. Everything else - routing, data fetching, build tooling - you configure yourself or add via third-party libraries.

This flexibility is useful when you have specific architectural requirements, but it means more setup, more decisions, and more maintenance.

What Next.js Adds

Next.js adds several critical capabilities on top of React:

File-based routing - your file structure becomes your URL structure

Server-side rendering (SSR) - pages rendered on the server for SEO and performance

Static site generation (SSG) - pre-built pages served instantly from a CDN

API routes - build backend endpoints in the same project

Image optimisation with next/image

Font optimisation with next/font

App Router with React Server Components for fine-grained data fetching

SEO Comparison

This is where the practical difference is most significant. A standard React SPA (single-page application) sends an empty HTML shell to the browser, which is then populated by JavaScript. Search engines can crawl JavaScript, but it is slower and less reliable than crawling HTML.

Next.js renders HTML on the server, so Google receives complete, crawlable content immediately. For any website where organic search traffic matters - which is most websites - Next.js is the clear choice.

Performance

Next.js applications consistently achieve better Core Web Vitals scores than equivalent React SPAs because of server rendering, automatic code splitting, and built-in image and font optimisation.

When to Use Plain React

A private internal tool where SEO does not matter

A highly interactive app (like a complex data visualisation dashboard) where client-side rendering is intentional

When integrating React into an existing non-Next.js stack

When your team has a specific reason to avoid the Next.js conventions

When to Use Next.js

Any public-facing website or application

E-commerce or marketing sites where SEO and performance are critical

SaaS products with a mix of public marketing pages and private app screens

Any new React project without a specific reason to avoid Next.js

Our Recommendation

Start new web projects with Next.js. The SEO benefits alone justify it for any public-facing product, and the developer experience improvements over plain React are significant. At Devarenalabs, we build with Next.js by default for all web projects. Get in touch if you want to discuss your stack.

Next.js vs React: Which Should You Use for Your Web App?