Why Client-only modules in NextJS? - Purpose & Use Cases

The Big Idea

Discover how to keep your Next.js app error-free while using cool browser features!

The Scenario

Imagine building a website where some parts need to run only in the browser, like showing a map or handling user input, but you try to run everything on the server first.

The Problem

Running browser-specific code on the server causes errors and crashes because the server doesn't have access to browser features like the window or document objects.

The Solution

Client-only modules let you separate code that should run only in the browser, preventing server errors and improving performance by loading these parts only when needed.

Before vs After

✗ Before

import Map from 'map-library';
export default function Page() {
  return <Map />; // breaks on server
}

✓ After

import dynamic from 'next/dynamic';
const Map = dynamic(() => import('map-library'), { ssr: false });
export default function Page() {
  return <Map />; // loads only on client
}

What It Enables

It enables smooth user experiences by safely using browser-only features without breaking your server-rendered app.

Real Life Example

Showing an interactive Google Map on a Next.js page without crashing the server or slowing down the initial load.

Key Takeaways

Browser-only code can break server rendering if not handled properly.

Client-only modules load code only in the browser, avoiding server errors.

This improves app stability and user experience in Next.js projects.